Could Leonardo DiCaprio's next big part finally win him an Oscar?

Leonardo DiCaprio is lining up an ambitious new role which could potentially see him in contention for the Best Actor Oscar that has so-far eluded him.

The 40-year-old star, who has appeared in many Oscar-winning movies but never converted the best actor gong for his performances, is set for the lead role in upcoming biopic ‘The Crowded Room’.

But while the magic, Oscar-winning word ‘biopic’ didn’t see him scoop a golden statue for his role as Jordan Belfort in ‘The Wolf of Wall Street’, ‘The Crowded Room’ may be a different matter.

In it he will play Billy Milligan, the first man ever to use having multiple personality disorder as a successful legal defence.

The movie will be based on the award-winning book ‘The Minds of Billy Milligan’ by Daniel Keyes, which explores Milligan’s trial for various felony charges, including armed robbery and three rapes on the campus of Ohio State University.

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His lawyers’ insanity defence saw Milligan become the first man to be acquitted of major felony charges due to his acute schizophrenia.

He was instead sent to a series of mental institutions, at which point he was diagnosed as having as many as 24 different personalities, ranging from Arthur, a prim and well-educated Englishman, a con artist called Tommy, a Yugoslavian communist called Ragen Vadascovinich and Adalana, a 19-year-old lesbian who he said had committed the rapes.

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Milligan died of cancer in a nursing home in Columbus, Ohio, in December last year, aged 59.

The film of Milligan’s life has been in various stages development since the early 1990s.

James Cameron co-wrote a screenplay from Keyes’ book on Milligan, while directors including Joel Schumacher, Nick Cassavetes, Danny DeVito and David Fincher have been attached in the past.

In the frame to play Milligan have been the likes of Brad Pitt, Matthew McConaughey, Johnny Depp, Sean Penn and John Cusack.

This time around, ‘Kidnapped’ writers Jason Smilovic and Todd Katzberg are penning the script, with DiCaprio taking on the hugely ambitious role.

The actor has spent over 20 years evading Oscars (both personally and in nominated movies), first off in 1994’s ‘What’s Eating Gilbert Grape’, where he was up for Best Supporting Actor.

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But despite further Best Actor nominations for ‘The Aviator’, one of his best roles, ‘Blood Diamond’ and ‘The Wolf of Wall Street’, he’s never managed to persuade Oscar voters to back him, notably when he was snubbed as ‘Titanic’ trawled.

Could this be his time?

He’s also producing the picture through his Appian Way production company, so maybe he’s going all in.

Ben Arnold writes for Yahoo UK Movies