The making of a serial killer: From student nurse to ruthless murderer, a full timeline of the horrific crimes Lucy Letby committed in plain sight - ending with her conviction as the most prolific child killer in modern day Britain

This is the full, shocking timeline of the year Lucy Letby spent killing babies on the neonatal unit of the Countess of Chester Hospital.

Beginning with her enrolment as an 18-year-old student nurse at the city's university, it details the horrific crimes she committed in 'plain sight' of colleagues who trusted her as one of their own.

Letby is seen to repeatedly betray both nurses and doctors alike, and to exploit the vulnerability and trust of the parents whose infants she was meant to be caring for.

The narrative ends with her conviction and incarceration as a serial killer, together with the revelation that police are now investigating the possibility that she attacked other infants earlier in her career.

Here, NIGEL BUNYAN looks back at the full timeline following the end of the trial:

Letby, from Hereford, at her graduation following a three-year nursing degree  

Letby - who grew up with two loving parents - is pictured as a young girl  

2008

September

Lucy Letby, a quiet, innocuous 18-year-old from Hereford, moves to Chester to begin a three-year nursing degree. It is the career she mapped out for himself while a student at Hereford Sixth Form College. 

She is three years behind another student at the college, the singer-songwriter Ellie Goulding.

Years later, when she is nine months into her killing spree, Letby will attend one of Goulding's concerts at the Liverpool Arena. During her time at university she will go on work experience at the Countess of Chester Hospital.

2011

September

The future killer finishes her degree and qualifies as a Band 5 nurse.

2012

January

Letby starts work at the neonatal unit of the Countess of Chester Hospital. She's living in nurses' accommodation at Ash House, within the hospital site, and qualifies as a mentor to new students 'fairly early on'. Just over a decade later she will tell a jury that she 'really enjoyed that aspect'. It will emerge after her trial that this is one of the years police are now investigating as part of a new inquiry into her activities.

2014

March 15

She goes to live alone in a flat belonging to one of her colleagues. She will be there until June 1, 2015.

2015

This is the second of the two years Cheshire Police are now investigating in the aftermath of the trial.

March/April

In court she will tell her barrister, Ben Myers KC, that from this point on her time is spent 'predominantly' looking after the sickest babies on the neonatal unit at the Countess of Chester.

At some point in the year Letby spends time at Liverpool Women's Hospital. Her time there is now being investigated as part of the new investigation.

May 31

Baby G, the most premature of the babies in the indictment, is born at Arrowe Park Hospital. She weighs 1lb 2oz and has a gestation of 23 weeks and 6 days. Letby will tell Mr Myers: 'She stood out as a baby who had complex needs and was a very premature baby.'

June 1

Letby moves back into Ash House. She'll remain there until moving into her semi-detached house in Westbourne Road, Chester, in April 2016. Her sadistic killing spree on the neonatal unit is about to begin.

June 5-7

Letby is in York on a hen party for her friend - and nursery nurse on the unit - Jennifer Jones-Key. A number of other Countess of Chester nurses are on the trip. They travel by train and end up drinking cocktails in Revolution Bar.

June 7

• 8.31pm: Baby A, a boy, is born a few moments ahead of his twin sister, Baby B. He is in good condition.

June 8

Letby has returned to work after the trip to York. Today she will claim the life of her first victim, Baby A.

• 5pm: Paediatric registrar David Harkness inserts a long line so Baby A can be fed the fluids he needs.
• 8pm: Baby A has been alive for almost a day. Up until now he has been looked after by Melanie Taylor. He is stable. Now Nurse Taylor hands over care to Lucy Letby and together they start the fluids via the long line.
• 8.26pm: Baby A collapses and Letby calls Dr Harkness over to his incubator. The infant is deteriorating rapidly. Resuscitation procedures are started and adrenaline is given to stimulate his heart. Harkness is joined by Ravi Jayaram and both notice an odd discolouration on the baby's skin, with flitting patches of pink over blue that seem to appear and disappear. Neither has previously seen such discolouration. The medics try desperately to save the baby's life, but none of the techniques that would normally help revive a baby are working.
• 8.58pm: Baby A is pronounced dead. He has died within 90 minutes of Letby coming on duty. Nick Johnson KC, prosecuting, said: 'That it is a hallmark of some of the cases in which Lucy Letby injected air into the circulations of some of these small babies'.

This graphic reveals how Letby was on duty at the time babies were dying 

June 9

In the aftermath of Baby A's death Melanie Taylor sends a WhatsApp message to Letby: 'I hope you are OK, you were brilliant'. Letby, though, is due to begin a night shift and is already thinking of killing the infant's twin, Baby B.

• 11.50pm: Letby's friend and colleague Nurse A is looking after Baby B. Shortly before midnight it's noted that her blood/oxygen levels have fallen to 75 per cent and the Cpap nasal prongs attached to her nostrils have become dislodged. Nurse Nurse A repositions the baby's head and the prongs and gives her additional oxygen.

A photograph issued by Cheshire Police showing nurse Ashleigh Hudson's recollection of the position of Child I's cot and the lighting in the nursery when she found her 'pale and floppy'

A fridge inside the neo-natal unit of the Countess of Chester Hospital, where Letby carried out her killing spree 

June 10

• 12.16am: Letby takes Baby B's blood gases even though she's not her designated nurse.
• 12.30am: Baby B's alarm sounds and Letby calls Nurse A over to the incubator. The baby has stopped breathing and a crash call is put out. It is about 28 hours since Baby B's brother has died.

CLICK HERE to listen to The Mail+ podcast: The Trial of Lucy Letby 

Letby's nursing colleague notices purple blotches and white patches all over the infant's body. Baby B is intubated and makes a quick recovery. The skin discolouration has reduced by the time the on-call consultant, Doctor B, arrives. She notes loops of gas in the baby's bowel.

When Dewi Evans, the prosecution's main medical expert, comes to review the case three years later he concludes that Baby B has been sabotaged both before and after midnight. Her airways may have been blocked and she may have had air injected to her bloodstream.

Professor Kinsey, a blood expert, says an injection of air into a vein can cause blood to cross from one side of the heart to the other without being oxygenated through the lungs. This would lead to the changes in skin colour seen by the medics. No blood disorder would account for Baby B's sudden deterioration.

Baby B continues to recover and will be discharged on July 9 and is now aged eight. She lives abroad with her parents.

• 3.31pm: On the same day Baby B has collapsed Baby C is born. His mother is a GP.

June 11

• 5.46pm: Letby is pressing to return to the 'front line' of Nursery 1, where the most vulnerable of babies are generally cared for. She messages one of her bosses, Yvonne Griffiths, to say: 'I think from a confidence point of view I need to take an ITU baby soon x'
• 9.48pm: Letby to Jennifer Jones-Key: 'I just keep thinking about Mon. Feel like I need to be in 1 to overcome it but E (Eirion Powell, unit manager) said no x'

Letby's parents, Susan and John, arrive at Manchester Crown Court on August 17. The couple supported her every day in court. A source told the Mail that Letby's mother was distraught when her daughter was arrested – wailing and crying, even telling police: 'I did it, take me instead,' in a desperate bid to protect her 

June 13

• 11pm: Nurse Sophie Ellis is in Nursery 1 giving Baby C his first feed of milk. She then goes briefly to the nurses' station where she hears Baby O's monitor go off. She returns to find Letby already in the room standing beside his cot. The killer says 'He's just dropped his HR and saturations: or something similar.'
• 11.09pm: Letby sends a message about the image of Baby A that she's had in her head from the week before, then says 'sleep well xx'.
• 11.15pm: Crash call. Senior house officer and the registrar, Katherine Davis, respond. Katherine tries three times to intubate him. She can't do because his vocal chords are swollen and blocking the route. They're 'stuck and swollen' before her first attempt. John Gibbs, one of the leading consultants, is called in and manages the intubation.

The attempts to save Baby C cross over into June 14.

June 14

• 5.58am: Despite a prolonged resuscitation they can't save him and C is pronounced dead.
• 8.48am: Letby to Jennifer Jones: 'I was struggling to accept what happened to Baby A. Now we've lost Baby C overnight & it's all a bit much. X'
• 8.57am: Letby again: 'Baby C is the little 800g baby, went off very suddenly, Sophie was looking after him. I know it happens but it's still so sad & cruel isn't it x'…
• 9.25am: Letby to her mum: 'We lost a little one overnight. Very unexpected and sad xxx'
• 9.41am: Letby to Jennifer Jones: 'I just keep seeing them both. No one should have to see & do the things we do. It's heartbreaking. But it's not about me. We learn to deal with it…'
• 9.45am: Letby to Jennifer Jones: 'It's not about me or anyone else, it's about those poor Parents who have to walk away without their baby. It's so unbelievably sad…'

Letby messages the news to Nurse A. Her friend urges her to try to sleep, then adds a sympathetic footnote: 'A really tough week for you'.

Mr Johnson will tell the jury that this time air has inserted into the baby's stomach via the NG tube, rather than into the baby's bloodstream. It is, he says, 'a variation or refinement of a theme Lucy Letby had started with the twins (A and B)'.

This graphic shows how Lucy Letby's horrific killing spree progressed throughout 2015 and 2016

June 20 

• 4.01am: Baby D is born by C section. She's a full-term baby born in good condition.
• 4.13am: At 12 minutes she goes floppy in her father's arms. Staff fail to give her antibiotics, then fail again to conduct an immediate review when she shows signs of respiratory distress. Eventually she is moved into Nursery 1. By now she has an infection.

June 21

Baby D is responding to treatment and not expected to deteriorate.

June 22

• 1.30am, 3am, 3.45am: Baby D suffers three collapses. In the second the infant is particularly distressed and crying. Staff are struck by the sight of mottling, poor perfusion and brown/black discolouration to her skin. Prosecutors say this was caused by Letby injecting air into her bloodstream while the baby's designated nurse, Caroline Oakley, was out of the room.
• 3.45am: As she collapses again Baby D is given CPR.
• 4.21am: Baby D can't be saved and treatment is withdrawn. She is pronounced dead four minutes later.

Medical expert Dr Sandie Bohin will tell Letby's trial Baby D was injected with air on one or more occasions. Between 3 and 5 mg/kg is enough to kill.

The paediatrician highlights D's heightened distress during her second collapse and says that in published cases of air embolus the patient suffers 'extreme distress and terror prior to collapse – signs demonstrated by D'.

June 30

• 9.49pm: Nurse A messages Letby: 'There's something odd about that night and the other 3 that went so suddenly'.

Letby responds: 'What do you mean?'

Nurse A: 'Odd that we lost 3 and in different circumstances… ignore me, I'm speculating'.

In the days after Baby D's death senior staff identify the first tenuous connection between Letby's presence and inexplicable collapses on the neonatal unit.

Lead consultant Stephen Brearey has been so concerned by the three deaths and one near-fatal collapse that he's asked Eirian Powell, the nursing manager, to carry out a review in the hope of identifying possible issues. She analyses which staff have been on duty at the relevant times, while also looking at such factors as incubator space and micro-biology.

Dr Brearey will tell Mr Myers: 'We were learning from every case we reviewed. (But) they were just pointers. They didn't always explain why these babies collapsed'.

Letby denied all the allegations as she gave evidence in the witness box

July 9

Baby B is well enough to go home. She is now safe from her would-be killer.

July 29

Twins Baby E and F, both boys, are born at a gestation of 29 weeks and five days. Baby E will die on August 4.

August 3

Letby is on the night shift.

• 9pm: The twins' mother comes into the unit to feed them expressed milk. She is shocked to find E screaming and with fresh blood around his mouth. Letby fobs her off and says Dr Harkness is coming down to review. It's a lie. Harkness isn't coming on duty until 10pm. The next time the mum will see her son he'll be in terminal decline.
• 9.11pm: Phone records confirm this is when the mum rings her husband in distress. The timing disproves Letby's claim that the mum came in at 10pm.
• 10.10pm: Dr Harkness is on the unit and sees 'a large vomit of fresh blood'.
• 11pm: There's a further loss of 13mls of blood. It sounds like a small amount, but it's a quarter of the baby's blood volume. Dr Harkness has never seen such a large bleed in so small a baby.
• 11.40pm: Baby E suddenly desaturates to 60 per cent. Medics notice he has a striking discolouration with flitting white and purple patches on his abdomen.

August 4

• 12.36am: Full CPR is begun because medics can't detect any cardiac output. The baby continues to bleed. Letby is involved in the resuscitation but at 12.38am is in Nursery 4 giving medication to another baby. The on-call consultant is called and she gives advice. She then attends and takes charge of the attempted resuscitation. It's hopeless.
• 1.23am: The woman consultant has to tap Dr Harkness on the shoulder to say it's time to stop.
• 1.40am: Baby E is pronounced dead. His surviving twin, Baby F, is moved into Nursery 2. Dr Harkness is so distressed by the episode he'll have to take time away on sick leave.

The woman consultant later steers the parents away from having a post mortem. Forensic pathologist Dr Andreas Marnerides says the absence of a post mortem is 'most unfortunate in this case'. It denies the prosecution a potentially key piece of evidence.

4pm: The prosecution case is that Letby injected a tiny amount of insulin into a bag of dextrose at some time between now and 1am on August 5. She will have known it would be fed to Baby F.

A note found in Letby's house which read in capital letters: 'I AM EVIL I DID THIS'

In another note, Letby had scribbled a jumble of words, with phrases like 'love', 'I can't do this anymore' and 'help me' written on it

April 2016 entries in a diary recovered from a chest of drawers at the home of Letby in Chester

Mr Johnson said: 'It's so sly, isn't it? Because it's going to be connected to the child at a time when the poisoner is not there'. This simultaneously diverts suspicion onto a colleague while deflecting it from herself.

August 5

• 1.54am: Baby F suffers an unexpected drop in his blood sugar and has a surge in his heart rate.
• 8am: Letby finishes her shift.
• 5.56pm: The medical team are so concerned about the infant's hypoglycaemic episode that they order a check of his plasma insulin level and the level of another hormone called C-peptide. Medics are unaware at the time, but this will prove that Baby E has been poisoned with manufactured insulin.

Meanwhile, a blood sample has shown a very low blood glucose level. It's so low that if left untreated it might have caused Baby F convulsions, coma, apnoea, irreversible brain damage and death'.

Baby F is now aged eight.

August 6:

Letby searches Facebook for the mother of the twins Baby E and Baby F. She'll do so eight more times from now until January 10, 2016. One is on Christmas Day 2015.

August 7

• 8.47pm: Baby I is born in Liverpool Women's Hospital. She weighs 2lbs 2oz. Though small, she is in good condition and does well right from the beginning.

August 18

Baby I is transferred to the Countess of Chester. There will be four separate occasions when Letby tries to kill the little girl. She finally succeeds at the fourth attempt.

September 7

Letby's first attempt on the life of Baby G (the little girl born on May 31). She is 100 days old and the killer is at the nurses' station working with colleagues on a banner. One nurse is baking a cake in celebration.

2am: Baby G is asleep but being fed milk via her NGT. A nursing colleague who is also Letby's best friend makes sure there's no residual milk in the tube and takes her scheduled one-hour break. She'll have asked someone to cover for her. Baby G is a well baby.

2.15am: The infant has two projectile vomits so forceful the fluid leaves the cot and splashes a nearby chair and canopy. Baby G stops breathing.

Alison Ventress, the on-call registrar and another good friend of Letby, is called and she sees that Baby G's abdomen is purple and distended.

Once the infant is settled she's transferred to the care of Lucy Letby. During the night she suffers further deteriorations that need intubation and ventilation. Dr Ventress notices bloodstained fluid in her trachea and a blood clot at the end of her breathing tube.

Medical experts will tell the trial Baby G has received an excessive volume of feed, as well as air, down her nasogastric tube.

September 8

In the early hours the child is returned to Arrowe Park where she recovers, returning to the CoCH on September 16.

A social media photo showing Letby smiling and laughing in the back seat of a car 

September 21 

• 8am: Letby starts a day shift, Baby G is so well she's about to have her immunisations. 
• 9.15am: Letby feeds the baby with 40ml via a NG tube.
• 10.20am: Baby G has two projectile vomits and goes apnoeic 'for six to ten seconds'. It's the same problem she had on September 7, this time following a documented feed by Letby. She recovers quickly.
• 3.30pm: Two doctors have been cannulating Baby G and mistakenly leave her untended on an open cot. The prosecution will say Letby takes advantage of that and attacks her behind a screen intended to shield infants from other families.

Letby herself says she found the baby 'dusky and blue and not breathing'. She calls for help and the baby is revived.

Letby messages Nurse A to say the baby 'looked rubbish when I took over this morning then she vomited at 9 and I got her screened…mum said she hasn't been herself for a couple of days'.

Nick Johnson said: '(Baby) G vomited because she had been given excessive air and milk'.

Letby was convicted of two counts of attempted murder of Baby G but not the third. She is now eight.

Letby in the dock at Manchester Crown Court on the morning of August 10  

September 29

Letby is on a day off. On the unit Baby I is eight weeks old and doing fine.

September 30

• 8am: Letby returns to work on a long day shift. She's Baby I's designated nurse in Nursery 3. By now Dr A has started work on the unit. 
• Mr Johnson said: 'Having failed to kill G and H, she turned her attention to Baby I. She falsified records along the way. She was the designated nurse on two of the four occasions she tried to kill her.
• 3pm: Around this time the baby's mother leaves the unit to collect her other children from school and take them home. Her husband is due to come in for the evening at 5.30pm. The prosecution say Letby used this as the 'perfect opportunity' to attack Baby I with an injection of air.
• 4.30pm: Baby I has a large vomit and is transferred to Nursery 1. Her NGT is aspirated and produces 'air+++ and 2mls of milk'. Once that is done her chest moves easily and the crisis has passed.
• 5.39pm: An x-ray reveals that at the time she crashed Baby I had a massive amount of gas in her stomach and bowels and that her lungs appeared 'squashed'.

OCTOBER

October 13

• 3.20am: Letby's second attack on Baby I. It's the occasion Letby claims to notice the baby is pale despite being further away than Ashleigh Hudson.
• Baby I needs full CPR. She has a bruise-like discolouration to the right of her sternum. Nursing and medical staff assume this is the result of chest compressions.
• 3.45am: The category of nursing care is raised a level and Letby becomes her designated nurse until 7.45am when she goes off duty. She is due back in at 7.30pm.

The prosecution case is that she has put excess air into the baby's stomach.

• 7.30pm: Letby is back on duty. She is Baby I's designated nurse for the coming night shift.

Lucy was suspected of having a secret affair with a married doctor who became her 'best friend' while she was murdering babies at work 

October 14

• 5am: The prosecution case is that Letby has injected the baby with more air around this time.
• 5.30am: She 'calmly' notes that Baby I's abdomen is distended.

Jennifer Jones-Key is due to get married the following month and Letby messages her excitedly about wedding rings.

• 7am: Baby I has a significant desaturation and needs CPR.
• 7.58am: The medics bring her back from the brink of death.

October 15

Baby I is transferred to Arrowe Park but returns to Chester on the 17th. She will be murdered on October 23.

October 22

During the evening the baby's observations are optimal and she doesn't need any respiratory support. Gibbs is happy with her. It's a 'virtually perfect scenario'. But then she suffers a series of collapses.

• 11.59pm: Just before midnight Baby I becomes unsettled. She's crying a 'relentless cry' and can't be settled. It's a cry Ashleigh Hudson hasn't heard before - 'relentless, almost constant and with no fluctuation'.

The baby collapses and needs cardiac compressions.

October 23

• 12.15am: The emergency continues. Dr Gibbs arrives. Baby I has a mottled blue appearance on her trunk and peripheries. Again an x-ray shows a massive distention of her bowel. Baby I is resuscitated and recovers to the extent that she is 'rooting' for a feed.

Dr Gibbs is perplexed. He can't understand what natural disease process would cause a baby to deteriorate so rapidly and yet recover with equal speed. 

The unsuspecting doctor gave Letby (pictured) a shoulder to cry on when she feigned upset after murdering two brothers – identical triplets – on consecutive shifts, in June 2016

• 1.06am: Ashleigh Hudson is at the nursing desk. She hears child crying. It's the same relentless cry. She thinks the baby is 'going to do it again'. Letby puts her off putting out a crash call, saying: 'She just needs to settle'.

But the infant crashes just as Nurse Hudson has anticipated. She RUNS to fetch Dr Chang who she knows is the other side of a set of double doors.

• 1.25am: Dr Gibbs arrives and notes purple and white mottling. The medics keep trying to resuscitate her for nearly an hour but it's futile. Treatment is withdrawn at 2.10am, the baby is pronounced dead at 2.30am.

During this final episode they don't have enough adrenaline and so have to access some emergency supplies. Baby I's chest has been rising and falling but there's no improvement.

Dr Chang finds Baby I's death inexplicable. Later the infant's mother will recall that Letby was 'smiling and kept going on about how she was present at (Baby) I's first bath and how much she had loved it'.

This has been Letby's final shift ahead of Jennifer Jones-Key's wedding on October 30th.

Johnson: '(Baby) I was born very early and very small. But she survived the first two months of her life and was doing well by the time Lucy Letby got her hands on her. What happened to her followed the pattern of what had happened to others before and what was yet to happen to others. All of a sudden out of nowhere came vomiting, breathing problems and critical desaturations'.

Letby's cruelty towards the infant was 'persistent, calculated and cold-blooded'.

• 2.06pm: A nursing friend of Letby's has heard of the death and asks whether she'd been looking after Baby I. Letby replies: '…I'm ok thanks. Ashleigh had her'. Letby knows this will help deflect suspicion if any arises.
• 3.55pm: Letby messages the same friend: 'Just don't think she was strong enough this time'.

October 31

• 3pm: Baby J is born at 32 weeks and two days. She has a necrotic and perforated bowel and has to go to Alder Hey to have a stoma fitted. She'll be transferred to Chester on November 10.

November 10

• 7.34am: It's Baby I's funeral later and Letby is on the unit taking a photo of the condolence card she has for the infant's family.

November 26

Letby is on the night shift.

Baby J is stable in Nursery 4 and due to go home the next day. Nurse Mary Griffith describes her as 'a joy to look after'. The infant's mum leaves the unit at the end of the day, intending to collect her at 8am.

November 27

• 4am: Baby J has an unexplained collapse that the prosecution say has 'all the hallmarks of an attack by Lucy Letby'.
• 5am: There's a second collapse, so Baby J is moved to Nursery 2.
• 6.56am: Baby J collapses again. Mary Griffith goes to her with Letby and finds the infant rigid with pale hands. Gibbs comes to help. He finds Baby J's oxygen dropping to unrecordable levels. Her fists are clenched, eyes deviating to the left.
• 7.24am: Another collapse. Again her fists are clenched and eyes rolling to the left. Dr Gibbs can't understand what is happening.

Medical expert Dewi Evans will say the infant has sustained 'some form of obstruction…such as smothering'.

Baby J is now aged seven and has never suffered a seizure since. The jury could not reach a verdict relating to the attempted murder charge against her. 

December 25

Letby spends Christmas Day with her parents in Hereford.

In a quiet moment she searches on Facebook for the mother of Baby E and Baby F. During her trial Mr Johnson will describe the mother as the woman who 'caught you in the act'. He'll add: 'You were a killer who was looking for your victims, weren't you?'

Letby kept souvenirs from parents, including this card thanking her 'for looking after us when were at Chester' 

December 31

Letby is back in Chester for a row of night shifts.

2016

January 10

Letby searches for the mother of the twins Baby E and Baby F. It's the ninth time since August 6.

February 17

• 2.12am: Baby K is born. She weighs 692g at 25 weeks gestation. Such an early delivery is normally planned to be at a tertiary centre, either Liverpool Women's Hospital or Arrowe Park Hospital on the Wirral, but there's been no time to get the infant's mum to either of them. As a consequence, Ravi Jayaram is present at the birth.
• 3.47am: Baby K's designated nurse, Joanne Williams, goes into the labour ward just to see her parents and update them on her progress. So three minutes later…
• 3.50am: Baby K is an hour and 38 minutes old. Ravi Jayaram is standing at the nurses' station but then realises Letby is alone with Baby K. When he goes into the nursery the infant's breathing tube is dislodged and she's collapsing. Letby tells him: 'She's just started deteriorating now'.

Despite his concerns, Dr Jayaram doesn't make a note of his suspicions.

• 6.10am: Letby logs on to Baby K's nursing record even though she's not her designated nurse. (There's a bit more detail on P.51 of the opening).
• 6.15am: There's another desaturation.
• 7.30am: Melanie Taylor takes over as Baby K's designated nurse. A few minutes later Letby is at the cot-side calling for help. This time the infant's breathing tube has supposedly slipped too far into her throat.

February 18

Baby K is transferred to Arrowe Park. She'll die there two days later.

Johnson: 'We allege she was trying to kill (Baby) K when Dr Jayaram walked in'.

Jurors could not reach a verdict on this case.  

March 10

Letby is at the Liverpool Echo Arena to see a concert by Ellie Goulding, who was three years ahead of her at Hereford Sixth Form College and is now an international star. The killer will stay the night in the city's James Street Hotel.

April 5

Letby moves out of her staff accommodation on the hospital site after collecting the keys to her new home in Westbourne Road, Chester.

April 7

According to the legal argument, Letby is moved to day shifts.

April 8

• 10.13am: Baby L and his twin brother Baby M are born at 33 weeks and two days gestation.

Mr Johnson said: 'It is the prosecution case that Letby attacked L first, with insulin, and then, whilst that attack was underway, also attacked M'.

• 6.15pm: Letby is unpacking at her new home. She has a 'Sweet Dreams' duvet and lays out her favourite Disney-style cuddly toys on top.

April 9

It's Grand National Day.

• 7.30am: Letby starts her shift.
• 4pm: Baby M collapses out of the blue and resuscitation attempts begin immediately. Dr Jayaram attends and notices unusual patches of discolouration on the baby's skin. Baby M doesn't respond well despite being given six doses of adrenaline in 25 minutes. Medics are about to withdraw treatment when he suddenly improves. Dr Jayaram suspects air embolus.

• 5.15pm: The Grand National starts at Aintree. Letby has a bet on the 33-1 shot Rule the World.
• 5.25pm: Rule the World wins the race and Letby wins £135. She invites her nursing pals on the unit round to her new home for prosecco and flavoured gin.
• 8.25pm: Dr Anthony Ukoh has just finished writing a record of Baby M's gas record on a paper towel. The prosecution will say that Letby deliberately hands around to get hold of both that and the record written up by her best friend A and then dropped into a confidential waste bin.
• 9.14pm: Letby writes a note to say that Baby M is tensing his limbs, curling his fingers and toes and rotating his hands and feet inwards - all indications that his brain has been starved of oxygen.

But he improves and by 3.30am is 'very active'. Mr Johnson said: 'He had a remarkably speedy recover from his near-death experience'. However, the collapse has caused him irreversible brain damage.

April 10

• 2.43pm: There's a message from Letby thanking Mary Griffith for her help and updating her re the twins.

June 2

1.42am: Baby N is born. He's only two weeks and three days short of being a full-term baby. But he's a haemophiliac. Letby will cause him to scream for half an hour.

Letby thinks she can use the baby's haemophilia as cover. If she causes him to bleed, she thinks, it will be put down to his condition.

In the evening she tells her best friend about the 'strange' Facebook message she's received from her close registrar friend, Dr A. The friend jokes about her 'flirting' with him and wonders whether she'll 'go commando'. At 8.39pm Letby replies to the latter with 'crying with laughter' emojis. But in court, incredulously, she claims not to know what the expression means.

And in another exchange over WhatsApp, Letby appeared to chat about her blossoming friendship with the doctor - who prosecutors said she had tried to impress by creating 'crisis situations' where they could work alongside each other to save the babies she had poisoned

June 3

• 1.05am: Baby N collapses. Dr Jennifer Loughnane writes in a note that he's 'screaming'. When she gives evidence at Letby's trial she will re-read her note, jolting back in her chair as she comes to the word 'screaming'.

Medical expert Sandie Bohin says that the screaming and half hour of crying is 'most unusual'. She adds: 'I have never observed a premature neonate to scream'.

June 14

By now Baby N is ready to go home. He's demanding expressed milk and taking more than the required volumes. The only thing holding him back is jaundice.

June 15

1am: Baby N looks 'very pale, mottled and veiny'. Letby's registrar friend, Dr A, wonders whether he is getting an infection. He runs a test that later proves negative.

5.10am: Letby messages her best friend who's on the night shift.

5.25am: The friend messages back: 'Baby N screened, looks like s**t'. Letby responds: 'Really?!'

7.12am: Letby is in 'extra early' for her day shift. Johnson says she's seen an opportunity to attack Baby N.

7.15am: Letby goes into Nursery 3, supposedly 'to say hello' to Jennifer Jones-Key. Nick Johnson says she's seen an opportunity to attack Baby N.

A few moments later Jones-Key has her back turned when Letby tells her Baby N is desaturating. Letby will claim in cross-examination that she's in the doorway at the time of the collapse.

Baby N is transferred to Letby's care and moved into Nursery 1. Dr A tries and fails three times to intubate him. He has to abandon the attempts 'due to blood present…trauma due to repeated attempts'.

2.15pm: Baby N desaturates again. This time two registrars and two consultants try in vain to intubate him.

Medical expert Dewi Evans suggests Letby has hurt the baby by thrusting a NGT down his throat. Nick Johnson: 'It's all your work, isn't it?' Letby: 'No, it's not at all'.

7pm: A transport team from Alder Hey arrives to help Baby N. Letby seems agitated, asking 'Who are all these people? Who are all these people'. A woman doctor thinks her behaviour is 'out of character'.

7.40pm: Dr Gibbs is in a huddle with the Alder Hey team discussing Baby N's transfer when the baby collapses again. The prosecution say this has been caused by Letby.

Baby N is revived and later in the evening will be taken to Alder Hey. Three days later he is well enough to go home. Letby was found guilty of the verdict count of attempted murder for Baby N but the jury could not reach verdicts on the other two counts. 

This has been Letby's last day at work before going on holiday to Ibiza. 

Letby struck before and after a holiday to Ibiza. Pictured is a bag she brought home from the trip 

June 21

2.24pm: Triplets Baby O, P and their brother, who will survive but can't be named for legal reasons, are born. Letby is still in Ibiza, enjoying tapas and taking a high-speed tourist ride on an orange inflatable.

June 22

Baby Q is born. He will be the last of Letby's victims.

• 2.11pm: Letby sends Jennifer Jones-Key a WhatsApp message: 'Yep probably be back in with a bang lol' She'll tell her barrister she's not planning 'anything terrible'. In cross-examination Mr Johnson said: 'Within 72 hours of that, two of the triplets were dead and Baby Q had collapsed'.

June 23

• 7.30am: Letby is back at work. She's in Nursery 2 with Baby O and his fellow twin Baby P.
• 9.30am: Dr Katarzyna Cooke has examined Baby O and says in a nursing note: 'No nursing concerns, observations normal'.
• 12.10pm: Letby is pleased to see that Dr A is back on the unit seeing Baby Q. Dr A is the medical lead today and he'll be in the same role tomorrow.
• 12.30pm: Prosecution say Letby over-feeds Baby O to sabotage him.
• 1pm approx: Melanie Taylor goes into Nursery 2, looks at Baby O and says to Letby: 'He doesn't look as well now as he did earlier. Do you think we should move him back to Nursery 1 to be safe?' Letby says no. In cross-examination she denies being dismissive, adding; 'That's Mel's opinion'.

• 1.15pm: Baby O suffers his first collapse. Letby records he's vomited undigested milk. The baby is reviewed by Dr A. According to the prosecution, she has a) sabotaged the baby and b) attracted the presence of the man she flirts with and confides in.
• 2.40pm: Baby O collapses again. He's mottled ++ and his abdomen is red and distended.
• 2.46pm: Melanie Taylor arrives shortly after the collapse and she, Letby and Dr A move him to Nursery 1.
• 3.49pm: Baby O collapses again. Dr A and his female colleague, Dr B, have met on the stairwell a few minutes earlier and arrive at Nursery 1 to see the infant being bagged by a nurse. Sats are very low, he looks pale. Dr B will tell the court: 'I don't know who the nurse was'. Dr A gives the baby morphine. Dr B is completely shocked because he'd been fine the day before and this is a totally unexpected collapse.

Both medics will tell the court there was good air, but the sats hadn't improved. Johnson explains: 'There's air going in and out, but the sats are not improving. This happens time and time again…'

• 4.15pm: There's a further collapse, with the first CPR at 4.19pm. Letby is there, so she and Dr A are both working on the baby she's fatally injured. He's oblivious to that.
• 4.30pm: Brearey has been in a meeting but is recalled to help. He notices a purpuric rash which is very rare in a neonate. It perplexes him because it's associated with good perfusion. The rash has gone by 5.15pm. It will turn out that the baby has sustained an injury to his liver, inflicted long before any CPR.
• 5pm – 8pm: Allegation is that at some point within this period Letby has over-fed Baby O's brother, (Baby P).
• 5.16pm: Second CPR for Baby O.
• 5.47pm: Treatment is withdrawn and Baby O dies.

Brearey is particularly concerned by Baby O's death because he'd previously been clinically stable, his collapse was so sudden and he didn't respond to resuscitation as he should have.

• 6pm: 13 minutes after murdering Baby O Letby is feeding his brother, (Baby P) some expressed breast milk. Except that what she's actually doing is deliberately over-feeding him.

While she's doing that John Gibbs is beginning a review of Baby P because he's concerned that Baby O has died in such unusual circumstances.

During the trial the prosecution ask Melanie Taylor whether O's collapse had been expected. 'No,' she says, but then Mr Myers jumps to his feet and complains to the judge that it's an unfair question. Nurse Taylor is having none of it and gives her view more forcefully. 'I disagree,' she says. 'I would not have expected that baby to collapse. I was surprised'. Mr Myers sits back down.

Letby will later claim to be deeply upset whenever a baby dies on the unit. 'To me personally it's devastating,' she says. 'You want to save every baby in your care. You're not supposed to watch a baby die'.

The post mortem on Baby O reveals a liver injury – damage in multiple locations on and in the liver, which had bled into the peritoneal cavity. At the time his bleeding is thought to have been caused by asphyxia, trauma or vigorous resuscitation. Mr Johnson says: 'Of course, no one would have thought that a nurse would have assaulted a child in the NNU of an NHS hospital'.

• 8.54pm: Dr A on FB to Letby: 'Are you OK?'

'F***ing hell, what happened?

Letby to Dr A: Can't think straight.

Letby to mum: 'Just as well I love my job!!'

Dr Brearey clearly suspects and wants a debrief the following day. But he'll be overtaken by events.

Medical expert Dewi Evans will say Baby O has died from a combination of intravenous air embolus - through the NG tube - and trauma. He doesn't think his liver injury was consistent with vigorous CPR and thinks it occurred before the collapse and contributed to it. It was probably the reason for his symptoms through the morning.

Dr Marnerides, the reviewing pathologist, certifies the death as 'inflicted traumatic injury to the liver and profound gastric and intestinal distension following acute excessive injection/infusion of air via a naso-gastric tube' and air embolus.

Letby will tell police in interview that Baby O's abdomen just kept swelling, and she suggested that sometimes babies can gulp air when they're getting help from Optiflow. This is not so.

A year later she'll carry out a Facebook search for the family surname.

While Letby's motive is not clear, the prosecution suggested she got a 'thrill' out of 'playing God'. She is pictured on a night out

June 24

The lead-up to Baby P's death - it's a Friday.

Overnight the 'problem' that Letby caused had been resolved. It will return within 90 minutes of her clocking back on.

• 7.30am: Letby is on a long day. She's the designated nurse for both Baby P and the third triplet– at least at least at the start of the shift. Later the triplet will go with Christopher Booth. Letby says in evidence that she was asked to continue looking after Baby P: 'I felt that was the right thing to do, for the parents to have that continuity'. In the morning, she claims, she has noticed that Baby P's abdomen was 'quite loopy – you could see the stomach had changed, was raised'.
• 8.30am: Letby tells Dr A in a Facebook message that she'd either sent or was sending her student with a baby who needs an MRI scan.
• 9.35am: There's a ward round on the unit and Dr Anthony Ukoh records Baby P self-ventilating in air but with a moderately distended abdomen and slightly mottled skin.
• 9.50am: The ward round is coming to an end when Baby P collapses. The medics who rush to the incubator are Dr A, Dr B, Dr Ukoh and Dr Cooke. Baby P is apnoeic and has a mottled appearance. His abdomen is becoming distended. He's intubated and efforts are made to transfer him to Arrowe Park. This is the day Dr Brearey had wanted to hold a debrief on Baby O, but instead he finds himself trying to save the second triplet.
• 11.30am: Baby P collapses again. He's given adrenaline and paralysed with a drug to aid ventilation. But he continues to deteriorate. Letby will claim at her trial: 'I just remember there being a general decline through the rest of the shift…There was an increasing sense of anxiety (on the unit) and a huge sense of relief when the transport team did arrive (from Arrowe Park). There are five Countess staff there throughout the day. The tension is so high that Dr B frequently goes out for a cigarette to try to calm herself and stay focused. Letby will tell Mr Myers that Baby P's needs were 'beyond our level of care'.
• Noon: Dr B has just had confirmation that the transport team is en route. She's hopeful Baby P will recover. As the minute hand passes the 12 she tells a group of nurses the good news. Letby looks up and asks 'He's not leaving here alive, is he?' Dr B is aghast. 
• 3.14pm: Baby P's final collapse. It comes just after doctors have reviewed him. Letby will tell Mr Johnson she has no recollection either of shouting for help or of the baby's breathing tube being dislodged. Mr Johnson tells her in cross-examination: 'The problem happened just after everybody left, just after you had said 'He's not leaving here alive, is he?' Letby: 'I don't agree with that'. Mr Johnson: 'Is this another case of bad luck, that it happened just after everybody left?' Letby: 'Yes'.
• 4pm: Baby P dies. Letby has achieved the murder she initiated nearly 24 hours earlier.

The baby's parents are beside themselves with grief, and Dr B senses their surviving triplet is now in mortal danger – from Lucy Letby. As the baby's father begins to beg Dr Rackham to take him in Bay P's place, Dr B adds her voice to the entreaties

She tells the court: 'Even though I didn't beg, and found a professional way of saying it, in my heart I just wanted him to leave too because that's the only way he was going to live. I wanted him to be in a safe place'.

Letby denies appearing 'very excited' in the aftermath of Baby P's death. At the time she dresses him and takes photos of him with his brother.

She then attends a debrief led by Brearey and Rackham and attended by other Countess Staff – including both Dr A and Dr B.

As the medics and nurses file out Dr Brearey picks up his phone and calls Karen Rees, the duty executive in urgent care, and tells her he doesn't want Letby coming back on duty the next day. Rees is already aware of his concerns. Rees turns him down.

Karen Rees was one of Letby's direct line managers. She was the former head of nursing for urgent care in 2015. She is pictured at her retirement party in 2018

He tells the jury: 'I was concerned about this because we'd already expressed our concerns to senior management about the association between Nurse Letby and the deaths we'd seen on the unit… Karen Rees was familiar with the concerns already…Karen said no…and that there was no evidence.

'I put it to her 'Was she happy to take responsibility for this decision in view of the fact that myself and consultant colleagues would not be happy with Nurse Letby going to work the following day'. She responded 'Yes, she would be happy'. I said 'Would you be happy if anything happened to the babies the following day'. She said yes. That's where the conversation ended'.

Later on Dr Brearey sees Letby and suggests she take the weekend off, to recover from the day's trauma. She declines; she'll be back at work in the morning. As she walks away she smiles and looks him confidently in the eye'.

• 5.04pm: Letby messages her best friend: 'Life is too sad. Lost another with 3rd going to women's (Liverpool Women's Hospital)'
• 5.12pm: The friend replies: 'Omfg. What the hell is going on! Will have big hug for you when I get there'.
• 10pm: Letby finishes writing up the medical notes she's started at 9.18pm. They're late because she had to go to A and E herself for a needle-stick injury. It's one of the needles for Baby P that's pricked her finger. She says she's fainted because of the stress of the day, plus she'd not eaten. 'The enormity of the past two days had taken its toll'.
• 10.06pm: Dr A is concerned for Letby and has offered her a lift home. Initially she refuses, but then changes her mind. He messages: 'Just outside the door'. She replies: '2 secs'.
• 11.39pm: 'Thanks for the lift…'

Confidential medical notes for both today and yesterday will be found at Letby's home when she's arrested. They've 'come home with me', she'll tell the court. It's one of her favourite expressions.

When the two main medical experts, Dewi Evans and Sandie Bohin, review Baby P's death they'll conclude that he'd had air injected into his stomach via a nasogastric tube.

Letby - wearing a blue hoodie with the strings covered in pink glitter - is taken from her house in handcuffs after being arrested by Cheshire Police 

Police outside an address on Westbourne Road in Chester in 2019 after Letby was arrested

June 25

• 12.10am: Letby to Dr A: 'I keep thinking of them both in the cot together – so peaceful yet beyond words for how awful it is'.
• 12.25am: Letby again: 'So sad. The family all thanked me when I took Baby P in dressed. And I know age doesn't make it any easier/harder but such a lot to go through at a young age'.
• 12.29am: Dr A replies: 'I don't know how it would be possible to get over losing a child, let alone 2'.
• 7.30am: Letby is on a long day shift and she's Baby Q's designated nurse. So despite Dr Brearey's warning to management, and his suggestion to Letby that she should take the weekend off, the killer is back on the unit.

There's an entry in her diary about a salsa session in Mold. However, she may be too focused on murder to go. Having killed Baby P the previous day, she's now going to try to kill Baby Q (Baby Q).

9am: Letby is scheduled to give Baby Q a feed, but the observations chart is never finished – 'almost as if she was interrupted by something', and there's no note in the milk row. The allegation is that she's injected Q with clear fluid and air while Mary Griffith has popped out.

When Mary returns she has her back to Letby who asks her to monitor Q while she goes to do cares for a baby in Nursery 1. This is her alibi.

9.01am: Letby is out of the room when Baby Q's alarm goes off. Mary calls for help and Minna Lappalainen responds. Q has been sick and the nurses use a suction catheter while giving him respiratory support. Letby appears soon afterwards. The prosecution case is that she has injected a clear fluid into his stomach a few minutes earlier.

There's a handwritten note by Nurse Lappalainen to say she's removed 'clear fluid +++' and 'NGT used to aspirate by Nurse Letby'.

However, there is also a computerised note. This has been made by Letby, and it reads: '09:10hrs Q attended to by SN Lappalainen – he had vomited clear fluid nasally and from mouth, desaturation and bradycardia, mottled ++. Neopuff and suction applied. (Dr A) attended. Air ++ aspirated from NG tube'.

Dr Gibbs sees this as 'no minor desaturation' and was 'not in keeping' with a baby such as Q who was getting tired. By now he has a 'heightened concern' about what is going on in the unit. Letby has her own heightened concern – that her colleagues are finally on to her.

The paediatrician asks who was looking after Q when he deteriorated. He does so because he knows word will get back to Letby.

In court Letby will tell Mr Myers that by now she felt 'drained and emotionally exhausted'. When cross-examined by Mr Johnson, she 'can't explain' why she hasn't filled in the saturations column. The barrister says pointedly: 'You were interrupted by Mary Griffith, weren't you?'

'No,' comes the reply.

Mr Johnson pushes harder. He suggests she has pumped Q with clear liquid while Nurse Griffith was out. It had to be clear liquid, he says, 'because milk wasn't an option'. 'You then tried to lay possible blame with both Nurse Griffith and another nurse…You were worried about it, weren't you, because the net was closing in on you, wasn't it Lucy Letby?'.

• 1.13am: Letby's best friend sends her a WhatsApp: 'Oh, who's looking after him? Mary?'
• 1.14am: Letby replies: 'Me, Minna has taken B off me so just got him. Almost had a tube earlier but gases improving'.
• 6.20pm: Baby Q has gone on to make a reasonable recovery through the day, but he is still on a ventilator and has poor blood gas. Johnson in cross-exam: 'You had nearly killed him, hadn't you?' Letby – no.

Mr Johnson said: 'Lucy Letby was worried when she went home that night – she must have got the impression that people were becoming suspicious of her'.

Letby sends a Facebook messages to Dr A…

• 10.46pm: 'Do I need to be worried about what Dr Gibbs was asking?'
• 10.54pm: Dr A to Letby: 'No'.
• 11pm: Dr A to Letby: What exactly did he ask?'
• 11.01pm: Letby replies: 'I walked into equipment room, he was asking Mary who was present in the room and how quickly someone had gone to him as I wasn't in the room. He asked who was there. I said I had popped out of room but Mary was in room and Minna at the desk'.

June 26

Letby is on a long day and from 7.30am she'll be looking after Baby BMC In Nursery 1. This will be her second shift after Dr Brearey's dire warning to management. According to her diary, she'll be out that evening: 'Las Iguanas – Minna'. Meanwhile, ahead of her day shift her late-night conversation with Dr A is continuing…

12.10am: Letby to Dr A: 'I keep thinking of them both in the cot together – so peaceful yet beyond words for how awful it is...the family all thanked me when I took (Baby) P in dressed'.

12.12am: Dr A to Letby: 'You are one of the few nurses across the region…that I would trust with my own children…You should do the APNP course, you'd be excellent'.

12.29am: Dr A to Letby: 'I don't know how it would be possible to get over losing a child, let alone 2'.

7.30am: Letby's day shift has begun and she's having a quiet time with Baby BMC. However, Dr A has noticed that Baby Q has a mildly dilated loop of bowel. He's concerned he may have NEC and will need surgery. So he's transferred to Alder Hey. It turns out he's ok and so comes back to Chester on the 28th. Q will have no further issues.

11.29pm: Letby is at home, typing a message into her phone that she'll never actually send. It's effectively a note to remind herself to write a Datix report she hopes will give her an alibi. She'll eventually fill in the Datix form on June 30.

June 27

The net is finally closing in on a woman who has been killing and maiming babies for a year. During the morning Ravi Jayaram is meeting the medical director about Baby N. A decision is taken not to accept him back from Alder Hey. It would appear the suspicions about Letby have reached a new height.

When Dr A gets to hear the news he thinks his superiors are likely to want a chat with him because he'd been the medical lead on both Thursday and Friday – the days O and P died. By now the killer knows of Dr Gibbs' concerns.

12.55pm: Letby to her best friend: 'Dr Gibbs was asking who was in room when Baby Q vomited and who was allocated who'. The two nurses are discussing filling in Datix forms to complain about conditions on the unit.

1.01pm: Letby messages her friend: 'Think we've got to cover ourselves as don't think E (Eirian) shows much support.

1.02pm: The friend messages back: 'Yeah I think Eirian would happily s**t on you at the moment'.

Later in the afternoon Eirian Powell is in her office and rings Letby. The conversation is a hammer blow and reduces the killer to a state of panic.

5.41pm: Letby messages Dr A: 'Eirian has just phoned telling me not to come in tonight & do days instead. I asked if there was a problem & she said No, just trying to protect me a bit & we can have a chat about it tomorrow but now I'm worried.'

Dr A sends two messages in an attempt to reassure her.

• 5.52pm: 'Lucy – you did nothing wrong at all'.
• 5.59pm: 'There is no problem…I can't (find) fault with your delivery of care to either baby last week. If there was anything I would have said so. Eirian knows you. Has there ever been a reason for you not to trust her?'

But Letby fears the worst and wants time to think of a way she can evade detection even at this late stage.

• 6pm: Letby to Dr A: 'I can't talk about this now'.

She then stays silent for twelve minutes. Then…

• 6.12pm: 'Sorry, that was rude. Felt completely overwhelmed & panicked for a minute. We all worked tirelessly & did everything possible, I don't see how anyone can question that. E has always been very supportive'.
• 6.16pm: 'I think I'm having a meltdown++ but think that's what I need to do'.

In cross-examination Mr Johnson asks: 'You knew they were on to you, didn't you?' 'No,' she replies.

• 11.29pm: Letby is on her phone, inputting a message she won't send but is intended as a reminder. The plan of action includes filling in a Datix on both Baby O and Baby P and 'a delay in people doing drugs'.

June 28

Letby is on a long day. Baby Q returns at some point in the day and she's his designated nurse in Nursery 2. She also has a baby in Nursery 1.

Baby Q has been her last victim. Tragically, the little boy has been left with irreversible brain damage. This will be confirmed by an imaging procedure carried out on November 16, 2019.

June 29

Letby is on a long day.

June 30

Letby is on a long day. It will be her very last shift on the unit. Her killing spree is finally over.

• 3pm: Letby fills in a Datix form that Mr Johnson suggests is cover for the fact that she's removed the bung and left an open port – 'a devious attempt to avoid suspicion'. 

Letby refers in a message to her best friend to a 'risk of air embolism'.

Mr Johnson will seize upon this. 'You had your thinking cap on, didn't you? You removed the port and covered it as a clinical incident. This is an insurance policy – so you could show the hospital was so lax…You knew at this stage you were being blamed for the collapses and deaths of these children'.

July 

At some point in July Letby is scribbling what the prosecution insisted all along was a confession.

'I AM EVIL I DID THIS', she writes. 'I killed them on purpose because I'm not good enough to care for them + I am a horrible evil person…The world is better off without me'.

But one particular word dominates the green Post-it note. Written in thick capitals and ringed in black, it reads 'Hate'.

July 1

• 12.01am: Dr A tells Letby about a rumour that Baby O had a ruptured liver. A woman doctor is upset, thinking she may have caused it when doing chest compressions.

July 5

Dr Brearey leads an afternoon debrief to review everything about Baby O and Baby P from birth onwards. Dr A will still be awake in the early hours of the next morning…

July 6

The registrar begins to tell Letby about the meeting. He asks for her discretion, unaware that years later the entire conversation will be played out in court. Oblivious to the harm she has done to the babies he has been so desperately trying to save, he compliments he her work as a nurse and assures her there is nothing to worry about. He is 'proud' of her care of Baby O and Baby P.

• 12.54am: 'You need to keep this to yourself…We reviewed everything. Room/meds/medical reviews and actions. We looked at all documentation med & nur.'
• 12.58am: 'If you've any doubt about how good you are at your job – stop now'.
• 1am: 'The documentation was perfect, everybody commented about the appropriateness of your request for a review of Baby O following vomit'.
• 1.02am: 'Your documentation of the resus/incubation/drugs was faultless'.
• 1.03am: 'There is absolutely nothing for you to worry about. Please don't'.
• 1.04am: 'There are going to be some recommendations based on staffing/kit but there was no criticism of either resus'.
• 1.05am: 'This is staying quiet until has been to exec's (sic). We're looking at (the care of the surviving triplet) on Thur.'
• 1.06am: 'E had nothing but good things to say about you'.
• 1.14am: Letby replies: 'I was one member of a huge team effort, but you know I've been carrying the worry of the 'what if I wasn't (good) enough – it's reassuring to hear that it doesn't appear that anything could have been done differently, or that I didn't act on or do something I should have'.
• 1.18am: Dr A: 'I was invited to attend because SB and A thought it was good consultant preparation for me. I gave extra details of both resus as they were required'.
• 1.21am: 'There were a few questions which were easy to answer, but the constant theme was how you and I dealt with Baby O deterioration and with Baby P resus. I felt proud for both of us'.
• 1.28am: Letby: 'That's good to hear. I'm glad you've had positive feedback too – you were fantastic, it was an awful situation but I wouldn't have wanted anyone else to be there – I now feel confident that we did absolutely everything & it's reassuring th know that the documentation reflects that'.
• 1.32am: 'There will be an inquest. We may have to attend'.
• 1.40am: 'I wouldn't have wanted anyone else but you to be looking after Baby O or Baby P. We do work well together!
• 1.42am: 'Baby Q care is going to be reviewed on Thur as well because of acute deterioration'.
• 1.42am: Letby: 'That makes sense'.

Dr A tells Letby that his own role in the care of Baby O, Baby P and Baby Q is being reviewed.

• 1.43am: 'They're looking at me because I was involved in all'.
• 1.53am: 'I ran Baby O & Baby P and was only Dr involved with Baby Q.

The registrar is still awake in the early hours.

• 2.01am: 'I was so sorry that you were upset when Eirian called that night when I knew you'd done a perfect job'.
• 12.21pm: Dr Brearey emails Dr A about the Baby O and Baby P cases they've discussed the previous afternoon. He thanks him for 'all your help in the last couple of weeks'. His email ends with a compliment: 'FYI also I thought your record keeping was clearer and more comprehensive than everyone else's'.

Texts between Letby and the unnamed doctor were read out in court. They appeared to show the doctor comforting the killer nurse as she feigned upset after the death of one of her victims

July 7

Countess of Chester Hospital downgrades itself from a Level 2 to a Level 1. Dr Brearey will say paediatricians requested the change in order to take pressure off the staff. He then fixes his gaze on Mr Myers and adds pointedly: 'And there were no more events after Miss Letby left the unit'.

July 14

Letby is having drinks with university friends. She'll tell the court they're the girls who were with her when she was studying nursing.

July 15

It's a Friday and Letby is off duty.

11.16am: Yvonne Griffiths sends out a round-robin email on behalf of the neonatal manager, Eirian Lloyd Powell. It's to break the news that each and every one of them will have to go through a period of clinical supervision. However, only one name is mentioned. Lucy Letby's. And it will turn out she's not just the first to go the process, but the only one.

'Hi Everyone,

'In preparation for the external review it has been decided that all members of staff need to undertake a period of clinical supervision. Due to our staffing issues it has been difficult to determine how we undertake this process. We can only support one member of staff at a time, therefore we have decided that it would be useful to commence with staff who have been involved in many of the acute events, facilitating a supportive role to each individual.

'Therefore Lucy has agreed to undergo this supervision first commencing on Monday 18th of July, 2016.

'I appreciate that this process may be an added stress factor in an already emotive environment, but we need to ensure that we can assure (sic) a safe environment, in addition to safeguarding not only our babies but our staff.

'This is not meant to be a blame or competency issue – but a way forward to ensure that our practice is safe. It will probably be developed into a competence based programme to be undertaken every 2-3 years in line with our mandatory update training.

'Kindest regards,

'Eirian Lloyd Powell'

In evidence, Letby will tell Mr Myers she isn't happy about the move; it's been imposed on her.

• 3.49pm: Letby messages her best friend: 'Hoping to get as much info together as possible. If they have nothing or minimal on me they'll look silly, not me'.

The texts end with Letby crowing that police 'have nothing or minimal on me' 

Letby sent this message to a colleague  

Letby celebrated a winning bet on the Grand National shortly after she attempted to murder twin boys

The nurse describes 'crying and hugging' the parents of Baby E, who died in her care 

In this string of messages, Letby tries to suggest the babies' deaths was linked to health problems 

After the deaths of Baby A and Bay C, says: 'There are no words, it's been awful' 

July 22

Letby is drinking prosecco with friends. At other times in the summer she'll be drinking cocktails in Kuckoo's bar in Chester.

August 

At some point in this month an MRI scan confirms that Baby G has sustained irreversible brain damage

August 8

• 11.31am: Letby WhatsApps her best friend: 'It's making me feel like I should hide away by saying not to speak to anyone and going on for months etc – I haven't done anything wrong… I can't see where it will all end'

• 11.56am: Her friend replies: 'I'm sure this time after xmas it will all b a distant memory'.

August 9

Letby is now being seconded to – of all departments – the Risk & Patient Safety Office.

• 2.19pm: Eirian Powell is sending another round-robin email to the neonatal nurses. 

'Hi All,

'There are currently opportunities for staff to apply for secondments throughout the Trust. It is (sic) therefore come at an opportune time for us and we were able to facilitate this for Lucy.

'Lucy is currently seconded to the Risk & Patient office for a period of 3 months.

'Laura is currently seconded to the Haemodialysis unit and will be returning in November 2016.

'Should anyone have an interest in other areas please discuss this further during your appraisal – or come to me directly.

'Kindest regards

'Eirian Lloyd Powell'

• Still 2.19pm: Letby immediately messages her best friend: 'Omg she's sent email about secondments!'

Her friend messages back with 'crying with laughter' emojis

Letby: 'Bl**dy hell fuming. I'm in email and makes it sound like my choice'.

September 7

Letby lodges a grievance against the NHS Trust. She is trying desperately to present herself as a dedicated, hard-working nurse who is being scapegoated by the unit's paediatricians.

Almost simultaneously she receives a letter from the Royal College of Nursing, informing her she's being blamed for the deaths.

September 22 

It's around this time that the instruction for her not to contact those on the unit aside from the three has been relaxed. She's sensing she has a level of support on the unit. On this date she sends a message to one of the three 'All ok with E (Eirian). Feel a bit more positive knowing she's definitely behind me'.

December 

This is when the grievance procedure was concluded. 

It is also the month a review into the high numbers is concluded by the Royal College of Paediatricians. The conclusion is that there's no single cause. It will be April 2017 before contact is made with the police, with a formal letter on May 2.

December 31

The woman who will go down in history as a sadistic baby killer is still upbeat about her chances of avoiding being brought to justice.

She writes on Facebook: '❤️I'm not the same person I was when 2016 began, but I'm fortunate to have my own home. I've met some incredible people and I have family and friends who have stood by me regardless – Thank you to those who have kept me smiling. Wishing Every Happiness for us all in 2017'.

She'll say in court that she's changed as a person and has 'lost confidence'.

2017

April 27

A number of staff from the Countess of Chester sit down with police. The hospital team is led by Tony Chambers, the chief executive, along with Ian Harvey, medical director. 

May 2

The chief constable of Cheshire, Simon Byrne, receives a letter from Ian Harvey asking his force to launch an investigation in the high number of deaths and unexplained collapses on the unit.

Tony Chambers (pictured) stepped down as the Chief Executive of the Countess of Chester Hospital after the police launched an inquiry into the baby deaths

Ian Harvey receiving a retirement gift in 2018

May 15

Drs Brearey and Jayaram attend a similar meeting. This time it's with Jayaram, Jeremy Holt and police officer Paul Hughes. The meeting covers a number of topics, with the two medics telling them about unusual rashes. Dr Jayaram mentions air embolism and there is talk of suspicions going as far back as Baby D.

Meanwhile, Letby is enjoying a series of rendezvous with Dr A, which will stretch into June. They meet in Harford, at the Cheshire Oaks designer outlet, and for a weekend in London. They plan a second weekend in the capital but it has to be cancelled because he has a medical appointment.

June 21

Letby writes her note to the triplets, two of whom she has murdered.

'Today is your birthday but you aren't here + I'm so sorry for that. I'm sorry that you couldn't have the chance of life, and sorry for the pain that your parents must experience every day…I don't if many people will be thinking of you today, or any day, but I will. I will always remember'.

June 23

It's the anniversary of Baby O's murder.

• 11.46pm: Letby is searching the triplets' surname. She tells Mr Myers: 'They were on my mind…It was such a harrowing experience seeing parents lose two of their children. In two days running, you don't forget something like that'.

June 24

The time on Letby's phone has run on past midnight. It's now the anniversary of Baby P's murder.

2018

Dr A may finally be waking up to Letby's true identity, or perhaps he's been taken into the confidence of his more senior colleagues. Either way, his time as a 'trusted friend' of Letby is drawing to a close. She'll tell the jury that the friendship 'fizzled out'.

The next time they meet will be in Court 7 of Manchester Crown Court. But he'll be behind a screen and the normally impassive Letby will be so overcome by emotion that she'll try to bolt through a side door of the glass-panelled dock.

April 20

Letby is researching the parents of Baby K – two years and two months after the baby's death. Mr Johnson: 'They were a couple who had passed through the NNU so quickly that even if she had met them she cannot have forged a relationship with them. When asked about this she said she did not recall'.

July 3

• 6am: Letby is asleep in her 'Sweet Dreams' bedroom when she hears a banging on her front door. She goes downstairs in a blue Lee Cooper leisure suit and is confronted by the sight of police officers on her doorstep. They say they're there to arrest her. She's allowed a few minutes to get ready before being led away in handcuffs. One officer is filming the procedure.

Once she's gone, her father, John, carefully tidies her bed, lining up the cuddly toys ready for her return.

2019

June 10

• 6am: Letby is in her childhood bedroom at her parents' home in Hereford. A team of officers drive into the quiet cul-de-sac and one of them knocks on the door. A few minutes later Letby is being driven away. This is her second arrest.

November 16

Brain imaging reveals abnormalities in Baby Q. They can be explained (but not necessarily proven) by excessive air and liquid being given via his NGT.

2020

November 10

Letby is arrested for a third time. Once again she is at her parents' home in Hereford. She will be remanded in custody from that point on.

2023

February 16

For four months Letby has appeared variously sullen or impassive in the dock. But Dr A is about to give evidence for the prosecution, and in the moments before he does so she realises with a start that he's chosen to speak from behind a screen. The knowledge that he can't bear to see her face makes her recoil in horror. She then tries to get out of the dock via a side door. It's not an attempted escape; it's a woman acting in extremis. As the trial continues, it will prove to be a rare show of emotion from the implacable, ruthless killer she has become. As Mr Johnson observes, she only cries for herself.

February 20

Mr Myers tries to cover off his client's meltdown the previous week by telling the jury she simply felt unwell.

June 30

Ben Myers KC finishes his closing speech.

July 3

The trial judge, Mr Justice Goss, begins his summing up.

July 10

The jury go out to consider their verdicts.

August 3

Having served on the landmark trial for almost 10 months, a woman juror reluctantly withdraws. The judge sympathises and makes it plain that she has 'very good personal reasons' for doing so.

The remaining 11 jurors – seven women and four men – must resume their deliberations without her. 

August 8

Mr Justice Goss gives the court a majority direction. 

Letby is found guilty of the attempted murder of Baby F and Baby L

August 11 

Letby is convicted of the murders of Baby C, of Baby I, of Baby O and Baby P, and the attempted murders of Baby M and Baby N. 

August 18

The jury return their final verdict and Letby is found guilty of the murders of three more infants.

She is convicted of the murder of Baby A, and the attempted murder of the child's twin sister Baby B. Letby is also found guilty of the murders of Baby D and Baby E.

In total, Letby is convicted of the murders of seven babies and the attempted murder of six others, following a 10 month trail at Manchester Crown Court.

The jury could not reach verdicts on six counts of attempted murder. 

WATCH THE MAIL'S LUCY LETBY DOCUMENTARY IN FULL HERE