Michael Douglas, 79, keeps it casual in unbuttoned shirt and cargo pants as he takes over pit lane at star-studded F1 Grand Prix in Monaco

Michael Douglas exuded effortless style as he arrived at the Formula One Grand Prix in Monaco on Sunday.

The Oscar winner, 79 — who recently admitted he gets mistaken for his children's granddad — appeared in high spirits as he strolled into the pit lane of the iconic race, clad in a relaxed unbuttoned shirt paired with cargo pants.

Despite sporting bright yellow lanyards dangling from his neck, he attempted to keep a low-key presence behind a pair of sleek sunglasses.

The actor was joined by a cavalcade of stars at the event, including Heidi Klum, Joe Jonas and Emily Ratajkowski.  

The international outing comes after Michael revealed the moment he realized his wife of 24 years, Catherine Zeta-Jones, was 'the one.' 

Michael Douglas exuded effortless style as he arrived at the Formula One Grand Prix in Monaco on Sunday

Douglas appeared in high spirits as he strolled into the pit lane of the iconic race, clad in a relaxed unbuttoned shirt paired with cargo pants

The Basic Instinct star fondly recalled that their romance was sparked by their mutual love for golf during an interview for daytime TV show Lorraine.

'You know, Catherine loves golf. That was actually kind of the closest we first got together,' he explained.

'Things were looking good and I said, "What do you think of golf?" She said "Oh, I love golf!," and I said "Oh, you do?" That's too good to be true.'

The Hollywood power couple met in 1998 at the Deauville Film Festival, where the actor was promoting A Perfect Murder with Gwyneth Paltrow.

Catherine was there supporting her film The Mask Of Zorro with Antonio Banderas.

Michael famously told her soon after they met, 'I want to father your children.'

The couple wed at The Plaza in New York City in year 2000 and welcomed son Dylan, 23, and daughter Carys, 20, soon after. 

Michael also shares son Cameron, 45, with his ex-wife Diandra Luker, and he confessed that he missed out on much of his eldest's childhood due to his busy Hollywood schedule. 

He said: 'Cameron suffered a lot from that time . . . I was just overwhelmed and overloaded by my work. And family was really taking third place after work, our country and then the family, as opposed to when Catherine and I got together.

'And you've done enough work already that you were looking more to enjoy the opportunity and the kids,' he said.

The Intolerable Cruelty actress also gushed over her long-time husband on their 23rd anniversary in November.

Catherine took to Instagram to share some of their wedding pictures as well as a selection of some of their past special moments together.

Sporting vibrant yellow lanyards dangling from his neck, he attempted to keep a low-key presence behind a pair of sleek dark sunglasses

The actor was joined by a cavalcade of stars at the event, including Heidi Klum, Joe Jonas and Emily Ratajkowski 

The international outing comes after Michael revealed the moment he realized his wife of 24 years Catherine Zeta-Jones was 'the one' (pictured in Cannes in May 2023)

The actor and his wife Catherine tied the knot in 2000 and share son Dylan, 23, and daughter Carys, 20 (pictured)

In one image, the Welsh star could be seen walking town the aisle with Michael at The Plaza in New York City in year 2000, while another showed them kissing during the ceremony.

Other snaps showed them on holiday together whilst in others they could be seen cozying up together. 

She captioned her post: 'Today we celebrate 23 years of marriage. Darling Michael, your Nobel Peace Prize awaits. 

'I love you…from your darling wife, a gold star Medal of Honor recipient.'