Johnny Depp: 'I was fascinated by mobster Bulger for years'
It's a role that's tipped to gain the three-time Oscar nominee Johnny Depp a fourth nod from the Academy yet the actor says an Oscar is "not the priority" when it comes to playing notorious gangster James "Whitey" Bulger in Black Mass.
The film, made by Crazy Heart director Scott Cooper, features an all-star cast including Benedict Cumberbatch, Joel Edgerton, Dakota Johnson and Kevin Bacon but it's Depp who is a frontrunner for the upcoming awards season as critics, including industry magazine Variety, hail his interpretation of Bulger as a "career-best work".
The Guardian's Peter Bradshaw adds that the actor is "horribly watchable" as the Boston crime boss, who was jailed for life in 2013 for the murders of 19 people.
Depp says he took on the role of Bulger simply "for the joy of the part, I was fascinated by him for years. He ended up on the FBI's Most Wanted list after informing for them. How did he evade justice for so long?
"You do things for the fans too, though I don't like that word," he continues. "I like to call them my bosses, because they're the ones who employ me. So you turn up to work for them."
Based on the book published in 2001, Black Mass: The True Story of an Unholy Alliance between the FBI and the Irish Mob, the film details one of the greatest scandals in FBI history: that from 1975 the bureau largely ignored the crimes of Bulger and his associates in return for informing on a rival mob in Boston.
When the cover-up was made public in 1994, Bulger went on the run for more than 16 years. He was eventually caught and tried, at the age of 82.
Depp says his challenge was to find "the essential humanity of the man - not to play him like a bad guy or a killer. It would have been too easy but that wasn't the way. He was still a human being who loved his mother, and his brother, and who took care of the people who lived around him.
"I think violence was his business and he didn't understand anything else. I call it the light switch going on and off - that he could make those violent decisions and then just carry on with his family."
The actor absorbed the few video and audio recordings that exist of Bulger, but reveals he did ask Bulger, now an 86-year-old inmate of a Florida jail, if they could meet.
"I did ask Mr Bulger if he would grant me some time, but he respectfully declined. Those were the exact words he used and I understood that very well. It was a very long shot anyway, because the idea of some guy playing him in a film was just weird.
"He was very gentlemanly about it - he just said he didn't like the book about him, and I can understand that he wouldn't be much of a fan."
Depp's trademark over a 30-year career has been to transform himself physically for his roles, including for Edward Scissorhands, Charlie and the Chocolate Factory, Alice in Wonderland, Sweeney Todd and Jack Sparrow in Pirates of the Caribbean.
The last two roles earned him two of his Oscar nominations, but director Cooper says his star has beaten his past form and his resemblance to the real Bulger is "uncanny", thanks to prosthetics used to recreate the mobster's unusually light skin and eyes.
Cooper recalls that Bulger's attorney was on set one day and "was spooked by Johnny's appearance".
"The lawyer said that the way Johnny looked, moved, and sounded - that it was Whitey Bulger."
"The physicality of the man was hugely important," Depp confirms. "I beefed up for it because he was a tough guy. I have some brilliant make-up artists who worked with me on Pirates of the Caribbean and we devised the look several times until one day I looked in the mirror and saw him.
"I had some letters from Mr Bulger's former associates saying I'd freaked them out. It's good to hear it."
Depp calls Cumberbatch, who plays Bulger's brother Billy, a Massachusetts Senator, "a beautiful man of exceptional talent. He became like a real life brother".
"The set-up we were playing was an unusual one - one brother becomes a politician, the other is king of the underworld. They still meet up for family dinners and church, just from opposing sides. It takes an actor with a lot of ability, like Benedict, to make that credible."
Cooper adds that while he expected Depp's fans to be showing up on filming locations, that instead it was Cumberbatch's followers "that were unlike anything I have ever seen in my life before".
"They were on every street corner. I don't think Benedict can understand it either."
At this year's Toronto Film Festival, Depp issued a tongue-in-cheek thank-you to Cooper "for reviving my career". The actor has had some critical and box office flops recently, most notably The Lone Ranger and Mortdecai.
On the subject of Oscars, last month Depp told BBC Radio 1's Newsbeat that he "didn't want to win one of those things ever," adding, "I don't want to have to talk. A nomination is plenty. I'm not in competition with anybody".
Previously he has said of his film choices: "I just stick to my guns and do what I want to do - sometimes people don't like it and that's alright."
But Cooper says: "Johnny is thrilled with the reaction (to Black Mass) and can't wait for people to see the film. He takes risks that most movie stars will not.
"He has had a career that is enviable by any actor's standards but he has privately said thank-you to me for the movie. I feel the more people see this the better."
Black Mass opens in the UK on 25 November.