Bradley Cooper talks about stepping out of his comfort zone in the Oscar-tipped film Silver Linings Playbook.
He was in The A-Team. He boosted his brain in Limitless. He lost his memory in The Hangover.
Now, in Silver Linings Playbook, Bradley Cooper takes on the challenge of playing a man with a bipolar disorder.
Cooper puts in a twitchy, mesmerising performance as ex-teacher Pat Solitano, who moves back in with his parents after eight months in a psychiatric institution.
Having had a mental breakdown, Pat is determined to rebuild his life and get back with his estranged wife.
"I've never really played a character with that dimensionality to him," the actor admits.
"Playing a guy who has no filter is an interesting format when you are playing a scene with others where you can improvise a lot."
Directed by The Fighter's David O Russell, the film also stars Jennifer Lawrence (The Hunger Games, Winter's Bone), Robert De Niro and Jacki Weaver (Animal Kingdom).
Based on the novel by Matthew Quick, Silver Linings Playbook won the top prize at Toronto International Film Festival in September. It was here in 2010 that The King's Speech began its prize haul en route to winning four Academy Awards in 2011.
Oscar buzz is already surrounding Silver Linings Playbook, with both Cooper and Lawrence's performances being touted for acting nominations. Lawrence plays Tiffany, a woman dealing with depression after the death of her husband.
According to director David O Russell: "Just as The Fighter to me was not about fighting, this movie to me is not about mental illness. To me, it's always about the people and the dynamic of the people."
Cooper describes working with Russell as "very unorthodox".
"You are in a vulnerable area because he demands that you are willing to get out of your head the minute you show up on set.
"You show up and it's BAM! - the crew's all around you, and it's happening now. It's almost like walking in and taking all your clothes off.
"It's an unbelievable experience. It's formidable and addictive."
Cooper is already signed up to work on the director's next film in 2013 about an FBI sting operation in the 1970s, starring alongside Christian Bale, Jeremy Renner and Amy Adams.
But how did he approach playing a character with a mental illness?
"You start with the script and then with the director, and you figure out who this guy is and where he comes from. We looked at a lot of videos and documentaries and literature and at whatever connections personally we could make."
He says he discovered a lot about the character once the filming had started.
"We modulated Pat within that first week of shooting. Initially he was a little Asperger-y and we thought that's not going to sustain for a whole movie - the audience will be empty by the end of it. It was about finding the right balance."
Cooper is currently filming The Hangover Part III, the third film in the comedy franchise.
Among his other film projects are indie drama Serena, set in depression-era North Carolina, in which Cooper reunites with Lawrence to play newlyweds looking to make their fortune in the timber business.
He will also be seen in the literary romantic drama The Words opposite Zoe Saldana; and he plays a police officer in Derek Cianfrance's thriller The Place Beyond The Pines, alongside Ryan Gosling, Rose Byrne and Eva Mendes.
This summer Cooper went back to his stage roots in the US, playing the lead role in The Elephant Man in Williamstown, Massachusetts. The actor hopes to take the play to New York's Broadway in the autumn of 2013.
"I loved it," he says. "It was challenging but at the same time the enjoyment superseded the darkness the challenge would bring over you. I love [John] Merrick, it's an honour to play him."
And Bradley Cooper fans in the UK will be pleased to hear he likes the idea of a stint on stage in London. "I'd love to do something in the West End, that would be incredible - living in London for five months or so."
Silver Linings Playbook is out in the UK on 21 November.