The Revenant has brought Leonardo DiCaprio his fifth Oscar nomination in an acting category and this weekend he's widely expected to finally take the Academy Award for Best Actor. Yet DiCaprio remains enigmatic.
More than 20 years ago director Agnieszka Holland got to know the young actor when she made period drama Total Eclipse, based on the Christopher Hampton play about the poets Arthur Rimbaud and Paul Verlaine. She says even then the instincts of a natural screen actor were obvious.
Set in 19th Century France, writer Verlaine became obsessed with Rimbaud who was a decade younger. The relationship was a complex blend of emotional dependence, addiction, literary ambition and sex.
The role of Rimbaud had been meant for River Phoenix until he died aged 23. Joining the project as director, Polish-born Holland knew she wanted DiCaprio as Rimbaud.
"Leonardo was always courageous in choosing roles," she says. "He was curious about things and wanted to explore.
"And there is something else. His father George, who has been a big influence over him, loved Arthur Rimbaud. He even edited a book about absinthe, the big drink of literary Paris. He thought his son couldn't possibly refuse the job.
"I went to a bookshop and found a t-shirt which had a drawing of Rimbaud on it and Rimbaud looked just like Leonardo. So I sent that to his agent and that was the beginning of our relationship."
But with its intense subject matter and its scenes of love-making between Rimbaud and Verlaine (played by David Thewlis), it was hardly a project you'd expect America's latest teen idol to alight on.
"Probably Leonardo was still 19, but not for one moment did I have the impression I was dealing with a newcomer," Holland says.
"He was one of the most mature actors I've ever worked with. His young age was more visible off the set: he would play tricks, about what he wanted to eat or whatever.
"But I had seen him act in This Boy's Life, with Robert De Niro, and in What's Eating Gilbert Grape [both in 1993]. His talent was obvious. After River died it was clear Leonardo was the most fascinating young actor there was - I think without him, I would never have made the picture.
"At the start of the story I needed him to convince as a 16 year-old. Somehow he could do that and, at the same time, be utterly mature in himself. I hadn't seen the film for a long time but recently I showed it to some students: I was still thrilled by his performance and I think it's one of his best.
"Today gay stories have become more popular. But at that time I knew that, for a California boy, it would be difficult to make this journey. David Thewlis was incredibly helpful.
"Talking to Leonardo I realised he has an incredibly deep emotional imagination. In performance he becomes a kind of medium - the soul of the character he's playing is entering his body."
Holland says DiCaprio has never been a classic American method actor, using personal experience to construct a character's inner life: "But he's doing some trick which is pretty mysterious to everyone watching - frankly even for the director. Look at him on screen and, for the moment of the shot, he really becomes the character."
Stacey Wilson Hunt covers Hollywood for New York magazine. She believes the fact most observers regard DiCaprio as a shoo-in for best actor this year has to do with more than just The Revenant.
"It's a good film, but in Hollywood there's been a sense for some time that Leo is overdue a major award. He hasn't made a really bad or dull film in more than 10 years - not something you can say of Tom Hanks or Tom Cruise or Will Smith. And people just like Leo, which in Hollywood is a big part of who wins what.
"Leo is a mystery - and people like mysteries. He's somehow managed to keep a relatively private life - despite the high-profile dalliances with supermodels. And in recent years his priority is more being an activist - it's absolutely clear when you hear him speak.
"That side of Leo is not just for show - he's given millions of dollars to environmental charities.
"People appreciate the way he keeps a distance from the film business. I was at a Screen Actors Guild event last year where he got an award for his humanitarian work. Perhaps because it wasn't televised he was very relaxed and it was touching the way he acknowledged the strength his parents had given him - especially because they were in the audience.
"His parents were very much bohemians who let him grow into his own person and you can see he remains very close [to them].
"He's learned to use the media for causes he's interested in. So his Hollywood friends include people like Mark Ruffalo, who's a big activist too. But for all that I think Leo will always be a mystery - either he's keeping something to himself, or he's incredibly grown-up now."
Holland says even in the 1990s, when they were shooting Total Eclipse, she could tell DiCaprio didn't want to remain the teen idol he was becoming - though he still had both Romeo + Juliet and Titanic ahead of him.
"Leonardo wanted to be a man. I know he didn't like being so slim and child-like, almost androgynous. After Titanic I believe he wanted to show he was a serious actor who could do big, serious parts. But in our film together, and then in Titanic, he's incredibly beautiful on screen. And Leonardo has a gift for lightness and humour and irony, even if that's not really part of The Revenant."
Why does Holland believe DiCaprio's life has never gone off the rails in public, as happens with some actors who find fame and wealth early?
"We made Total Eclipse in Paris and Brussels and Djibouti, but wherever we went it was clear he had a solid grounding. He was true to his roots and loyal to his family, and he still is. He respects people not because of their celebrity or money, but because of their human qualities - he's not a snob.
"When someone has a very special talent you can say it was given by God. Of course he's worked to develop his talent over the years. But if you look back, even before Total Eclipse, it was there from the very beginning."