You cannot argue with her beauty, nor with the elegance with which she turned out to promote Kevin Costner's new Western epic, Horizon: An American Saga, in Cannes this week, stealing the show in diaphanous, pale blue chiffon by French fashion house Chloe.
At 42, she's never looked lovelier and with boyfriend Oli Green, 27, and her charming 11-year-old daughter Marlowe joining her on the red carpet, Sienna Miller has never looked happier either.
It may be that acting acclaim still eludes her at this, the third — or maybe fourth — time of asking. The critics don't think much of the film, or of her in it.
But, actually, does it matter? For Sienna, the posh boho girl, who has been engaged four times while fitting in flings with actors Daniel Craig and Balthazar Getty (a scion of the oil dynasty), has lived her life to the full, embracing one adventure after another. And she does not regret a thing.
Her new boyfriend, Oli, an actor who is 15 years her junior, is just like her — instinctive and a free spirit. In an interview earlier this year she explained: 'I think you either live your life with caution or you take risks.'
![At 42, Sienna Miller has (pictured) never looked lovelier and with boyfriend Oli Green, 27, (pictured) and her charming 11-year-old daughter Marlowe (pictured) joining her on the red carpet](https://i.dailymail.co.uk/1s/2024/05/22/22/85221827-13449167-image-a-90_1716411716268.jpg)
At 42, Sienna Miller has (pictured) never looked lovelier and with boyfriend Oli Green, 27, (pictured) and her charming 11-year-old daughter Marlowe (pictured) joining her on the red carpet
![Sienna Miller and Kevin Costner attend the "Horizon: An American Saga" Red Carpet at the 77th annual Cannes Film Festival at Palais des Festivals](https://i.dailymail.co.uk/1s/2024/05/22/22/85221831-13449167-image-a-91_1716411724386.jpg)
Sienna Miller and Kevin Costner attend the 'Horizon: An American Saga' Red Carpet at the 77th annual Cannes Film Festival at Palais des Festivals
![Sienna, the posh boho girl, has been engaged four times](https://i.dailymail.co.uk/1s/2024/05/22/22/85221829-13449167-image-a-92_1716411727889.jpg)
Sienna, the posh boho girl, has been engaged four times
![Sienna Miller (L) and US director Kevin Costner (R) arrive for a screening of the film 'Horizon: An American Saga'](https://i.dailymail.co.uk/1s/2024/05/22/22/85221845-13449167-image-a-93_1716411730893.jpg)
Sienna Miller (L) and US director Kevin Costner (R) arrive for a screening of the film 'Horizon: An American Saga'
![Sienna Miller departs the "Horizon: An American Saga" Red Carpet at the 77th annual Cannes Film Festival](https://i.dailymail.co.uk/1s/2024/05/22/22/85221851-13449167-image-a-94_1716411733245.jpg)
Sienna Miller departs the 'Horizon: An American Saga' Red Carpet at the 77th annual Cannes Film Festival
She added that whatever success, or otherwise, her choices are met with, she is finally at peace.
'For the longest time, I felt the need to really prove something, and I can see that reflected in the choices that I made. I pursued roles that were very heavy and very dramatic and challenging emotionally because I felt that I was probably seen as frivolous. I'm now completely over that.'
Most significantly, of course, she finally has a settled personal life, which is bringing her joy. Her family unit, beyond Oli and the baby girl they welcomed in December, includes Marlowe and her father, Sienna's ex, Tom Sturridge, to whom she remains close (they dated from 2011 to 2015).
Lucky Marlowe has access to both Sienna's wardrobe and that of Alexa Chung, the model and TV presenter, who is engaged to Sturridge. Sienna is said to be delighted by the match.
When she decided to relocate from New York back to London almost two years ago, Sturridge agreed to do the same in order to make it easier to share custody of Marlowe, known as 'Mar'.
![The critics almost universally don't care for Costner's film Horizon, an old-fashioned Western, and find her role in it, while well-executed, 'a cliché'](https://i.dailymail.co.uk/1s/2024/05/22/22/85221901-13449167-image-a-95_1716411907955.jpg)
The critics almost universally don't care for Costner's film Horizon, an old-fashioned Western, and find her role in it, while well-executed, 'a cliché'
![Kevin Costner and cast members Sienna Miller, Georgia MacPhail, Jena Malone, Abbey Lee, and Isabelle Fuhrman pose on the red carpet during arrivals for a screening](https://i.dailymail.co.uk/1s/2024/05/22/22/85221895-13449167-image-a-96_1716411909956.jpg)
Kevin Costner and cast members Sienna Miller, Georgia MacPhail, Jena Malone, Abbey Lee, and Isabelle Fuhrman pose on the red carpet during arrivals for a screening
Although Sienna bought a 16th-century thatched-roof cottage in Buckinghamshire, which she showed off in the pages of top property magazine Architectural Digest in 2022, she, Green and the children are now thought to be living in West London, with her ex and his fiancée Alexa only a few miles away in North London. There was a slightly tricky period during lockdown, when the exes ended up living together with their then partners in New York. Sturridge was with Uma Thurman's daughter, Maya Hawke, and Sienna was dating Lucas Zwirner, a musician.
Sienna said later: 'I had my then boyfriend, and Tom's then girlfriend came and . . . it was definitely eccentric. I can't go into detail but the wheels came off and everything went horribly wrong.'
She added that, on the upside, 'it will make a fantastic play'.
Her new daughter — whom Sienna brought to Cannes but not on to the red carpet — is adorable, of course (the couple have yet to announce her name).
And in Oli Green she has found someone every bit as easygoing as she is. There's a sense that neither of them are too driven, and their life will be all the richer for it.
Actress Emily Blunt, who is a close friend, told Vogue recently: 'I see so much of her in him, in that free-spirited, curious, guileless thing that he has.
![Miller stars in Horizon: An American Saga](https://i.dailymail.co.uk/1s/2024/05/22/22/85221903-13449167-image-a-97_1716411913841.jpg)
Miller stars in Horizon: An American Saga
![Kevin Costner and Sienna Miller](https://i.dailymail.co.uk/1s/2024/05/22/22/85221889-13449167-image-a-98_1716411917721.jpg)
Kevin Costner and Sienna Miller
'He's the kind of guy you could just bring anywhere, and everyone would love him.' Blunt also notes that Sienna always wanted another child — saying she felt guilty about not giving Marlowe a 'partner in crime'.
'We've talked about it for years,' Blunt said. 'She just needed the right person, and I really see that in Oli.'
Sienna burst on the scene — a stylish, smiley blonde whose penchant for boots and studded belts launched a million imitations — in the early Noughties. Her father Edwin is an American dealer in Chinese art, while her mother, Josephine, a former model, was once personal assistant to David Bowie. Born in New York, she was raised between London and Wiltshire after her parents split when she was five.
A rebel at Heathfield boarding school in Ascot, she went on to study drama at the Lee Strasberg Institute in New York. Her big break came in 2004, at 23, when she played opposite the already-famous Jude Law in a remake of the classic film Alfie.
A starlet was born, and with Law freshly divorced from actress Sadie Frost, their relationship seemed meant to be.
But to Sienna's humiliation, the following year Law was caught with his trousers down in the company of his children's nanny. She later had a fling herself — with Law's close friend and future 007 Daniel Craig, with whom she starred in crime film Layer Cake.
![Jena Malone, Isabelle Fuhrman, Ella Hunt, Georgia MacPhail, Sienna Miller, Abbey Lee Kershaw and Wasé Chief attend the "Horizon: An American Saga" Photocall](https://i.dailymail.co.uk/1s/2024/05/22/22/85221897-13449167-image-a-99_1716411923941.jpg)
Jena Malone, Isabelle Fuhrman, Ella Hunt, Georgia MacPhail, Sienna Miller, Abbey Lee Kershaw and Wasé Chief attend the 'Horizon: An American Saga' Photocall
![British actress Ella Hunt and Coleman and British-US actress Sienna Miller arrive for the screening of the film "Horizon: An American Saga"](https://i.dailymail.co.uk/1s/2024/05/22/22/85221879-13449167-image-a-100_1716411926981.jpg)
British actress Ella Hunt and Coleman and British-US actress Sienna Miller arrive for the screening of the film 'Horizon: An American Saga'
It was reported that she had found herself pregnant and chose not to have the child. In an interview she said: 'People on the street would shout 'baby killer' at me. That's fine. That's their opinion. You know, there's always going to be people like that.'
H er romance with Law always seemed unpredictable. In one of their periods apart she dated Notting Hill actor Rhys Ifans. Her image, too, became increasingly unconventional. She was known for living in wild style, once admitting a fondness for magic mushrooms, and claiming to have experimented with morphine to see what heroin would be like.
She later reflected on 'a couple of years of absolutely chaotic behaviour. I did not know which way was up or down.
'I was, I suppose, in the midst of an absolute breakdown on every single level. I couldn't say what had actually happened. My way of dealing with that was to slightly lose it. And I did, I was running around the Vanity Fair party with no shoes on and getting really p****d'.
In 2008, after splitting from Law for good, she had a romantic fling with Balthazar Getty and was photographed topless on holiday with him.
An heir to an estimated £2.5 billion fortune, he was married with four children. The liaison fizzled out and Getty went back to his wife Rosetta.
In an interview with GQ magazine in 2009, she admitted that the stories 'probably looked awful. I probably seem like not a particularly nice person, not a girl's girl'.
![Sienna Miller arrives for the screening of the film 'Horizon: An American Saga'](https://i.dailymail.co.uk/1s/2024/05/22/22/85221893-13449167-image-a-101_1716411933085.jpg)
Sienna Miller arrives for the screening of the film 'Horizon: An American Saga'
![Sienna Miller, Kevin Costner, Wase Chief and Luke Wilson attend the "Horizon: An American Saga" Red Carpet at the 77th annual Cannes Film Festival](https://i.dailymail.co.uk/1s/2024/05/22/22/85221887-13449167-image-a-102_1716411936413.jpg)
Sienna Miller, Kevin Costner, Wase Chief and Luke Wilson attend the 'Horizon: An American Saga' Red Carpet at the 77th annual Cannes Film Festival
In terms of her career, she cites her 2009 role in GI Joe: The Rise Of The Cobra as a low point. 'It had become difficult for me to get the work I wanted,' she said.
'I sabotaged things. I burnt a lot of bridges . . . I wasn't behaving the way you should. I'm very lucky to have a second chance.'
A stint on Broadway in After Miss Julie was well received and she was better still in the 2011 West End production of Flare Path, directed by Trevor Nunn. Professionally she began to get the roles that had eluded her and her private life also seemed to settle as she got together with Sturridge. Marlowe was born in 2014.
That same year, Sienna starred in American Sniper, opposite Bradley Cooper, and in Foxcatcher. Both won her plaudits. She even took on the demanding role of Sally Bowles in a Broadway production of Cabaret. She had passed 30, she said, and now was her time. Yet, once again, that promise didn't quite translate into the big leagues.
In 2022, Vogue magazine pronounced a 'Siennaissance' after the modest success of the Netflix drama Anatomy Of A Scandal, a Westminster-set thriller. And again this year, only a few months after having a second child, the idea of a Sienna moment is in the air again. She has new friends, including actress and model Cara Delevingne and 'It-girl' Lady Lola Bute, whose recent 25th birthday party had tinges of decadent movie Saltburn and a guest list to die for.
![Greta Gerwig, Sienna Miller, Chemena Kamali, Emma Mackey and Zoe Saldana attending the Metropolitan Museum of Art Costume Institute Benefit Gala 2024 in New Yo](https://i.dailymail.co.uk/1s/2024/05/22/22/85222001-13449167-image-a-105_1716411970829.jpg)
Greta Gerwig, Sienna Miller, Chemena Kamali, Emma Mackey and Zoe Saldana attending the Metropolitan Museum of Art Costume Institute Benefit Gala 2024 in New Yo
![Sienna Miller attends the "Horizon: An American Saga" Photocall at the 77th annual Cannes Film Festival](https://i.dailymail.co.uk/1s/2024/05/22/22/85221875-13449167-image-a-104_1716411952959.jpg)
Sienna Miller attends the 'Horizon: An American Saga' Photocall at the 77th annual Cannes Film Festival
Friends say Sienna is 'effervescent' and the life and soul of every party. Romantic disappointments don't seem to have dimmed her love of a good night out.
The critics almost universally don't care for Costner's film Horizon, an old-fashioned Western, and find her role in it, while well-executed, 'a cliché'.
She plays settler Frances Kittredge, who ends up hiding in a hole under the floorboards and having to use a gun barrel as a breathing tube. As an image of a woman driven to extremes just to survive, that takes some beating.
But, in reality, glorious Sienna can breathe freely. She's making money as never before, thanks to her fashion deal with Marks & Spencer.
Her first collection came out this autumn to great acclaim. The association has been successful and is thought to net her over £500,000 a year.
She is developing her own range of skincare, which seems an obvious path to go down. She might say her extraordinary glow is all down to Charlotte Tilbury cosmetics, but women want to know the real secret of how she's bounced back to look quite so film-star gorgeous just months after giving birth to her second child in her 40s.
She's also got a West End gig lined up, a stage adaptation of the 1940s Cary Grant and Rosalind Russell vehicle His Girl Friday that will likely open in London in 2025. The big question is, who will play her Cary Grant?