He made his name in The 40-year-old Virgin and as an idiot weatherman in the Anchorman movies. So what is Steve Carell doing playing wrestling-obsessed millionaire and murderer John du Pont in Bennett Miller’s Foxcatcher?

‘It was a huge opportunity for me. I didn’t think twice about it. It would have been crazy not to accept it.” Steve Carell is talking about his role in Foxcatcher, playing the wrestling-obsessed millionaire John du Pont, who in 1996 shot dead Dave Schultz, the coach of the US Olympic wrestling team that Du Pont had set up.

Despite his track record of goofy comic turns and nice-as-pie straight men, Carell had no qualms about playing the role of a deeply disturbed killer. It’s actually turned out pretty well, career-wise: this spruce, neatly dressed 52-year-old already has a Golden Globe nomination under his belt, and there’s serious talk of an Oscar run.

That, no doubt, explains Carell’s serious mien: Foxcatcher marks a new development in his profile. He’s done drama before, but always with a comedic edge – Crazy, Stupid, Love, for example, or The Way, Way Back. Foxcatcher is downright disturbing, a slowly accreting study of dysfunction and dependence that erupts in a startling act of violence. There are one or two half-smiles in it, but none associated with Carell’s Du Pont, who cuts a disturbing figure throughout.

Carell is considered in his analysis of Du Pont, an eccentric individual to say the least, who was described by psychiatrists as psychotic and a paranoid schizophrenic during his trial after the Schultz murder. “I never saw him as a villain, and I didn’t want to depict him in that way,” says Carell. “Here was a guy who was the product of his upbringing, his enormous wealth. He was isolated to a great extent from many of the things that he longed for – and it was compounded with mental issues, of course. He was someone who didn’t possess the tools to achieve what he wanted out of life; and in that regard, incredibly heartbreaking.”

Facebook Twitter Pinterest Steve Carell in Foxcatcher. Photograph: Photograph: Allstar

Foxcatcher’s main narrative deals with Du Pont’s installation of the gold-medal-winning Schultz brothers – first Mark, then Dave (Channing Tatum and Mark Ruffalo) – on his estate in Pennsylvania, part of his increasingly capricious plan to dominate the US Olympic team. By dangling large sums of money, Du Pont could buy up the largely college-based, amateur freestyle wrestlers who, the film is at pains to make clear, are very different from the razzle-dazzle pantomime acts of the pro circuit. (That particular branch of the sport, of course, has been mined in the Mickey Rourke film The Wrestler.)

Carell says he and Foxcatcher’s director Bennett Miller – previously responsible for Moneyball and Capote – didn’t want to get into all “the lurid details”; meaning that, while Foxcatcher shows Du Pont imposing himself as a wrestling coach, giving himself odd nicknames, and devoting time to other hobbies such as the appreciation of heavy weaponry, it’s apparent that considerable pruning has been done. Perhaps most notably, the film makes no reference to Bulgarian wrestler Valentin Jordanov, with whom Du Pont was apparently obsessed, and for whom, the real-life Mark Schultz suggests, Du Pont committed the murder, as a “bizarre gift”.

Carell takes the approach – clearly following Miller’s lead – that less is more as far as his portrayal of Du Pont. “Du Pont’s behaviour in real life was much more outrageous than what is depicted in the film. It would make it a more difficult leap for an audience to accept. How could these people stay within his circle in the face of the delusional, aggressive behaviour he exhibited? How could these people be so complicit? There was a transaction there; they all had a part in it, they all accepted it, they accepted the benefits.”

They even shot a sequence in which – following a well-documented episode where Du Pont was given a wrestler’s haircut by Mark Schultz – the multimillionaire picked up a machine gun and began wildly firing from a veranda at imaginary enemies. “Didn’t get used,” says Carell. “It wasn’t Bennett’s agenda. It’s such a spare kind of movie. As a director, there’s nothing extraneous there. It’s very clean, very quiet. That was the approach to Du Pont as well, to reveal bits and pieces of him, and not reveal too much.”

Facebook Twitter Pinterest Carell in his breakthrough role, The 40-year-old Virgin. Photograph: Allstar/UNIVERSAL/Sportsphoto Ltd./Allstar

Dwelling extensively on Du Pont’s psychosexual disposition would have made Foxcatcher a different film, but Carell – perhaps betraying a little of the uncertainty of someone dipping their toes into water outside their comfort zone – appears somewhat in awe of his director. He is fulsomely outspoken in his praise for Miller (“a special and talented film-maker”) and still appears slightly baffled how he got the role at all. “He saw in me the potential to do something I hadn’t done before.” Carell says his agent put him forward for the role without telling him; when he got the call from Miller it was “a pleasant surprise”. He also seems happy to be steered by Miller’s assessment of his career profile: “Bennett says I have a benign public persona, and Du Pont did too. I think that’s why he cast me.”

Miller is not wrong. Carell, for all his renowned comedy-improv skills, exudes a niceness that verges on the bland. It’s hard enough to connect him with the stellar goofiness of Anchorman’s Brick Tamland, let alone the creepy self-infatuation of John du Pont. In the nicest possible way, Carell gently knocks back any suggestion that he has “dark places” himself that may have proved rewarding to disinter. “That would be a discussion with a therapist,” he says coyly. “But I didn’t need to do anything. Just to feel those rhythms, and feel where Bennett is going, and what the other actors are doing.”

The closest Carell gets to suggesting anything remotely off-beam is the effect on his fellow cast members when he climbed into the unpleasant teeth-hair-skin additions necessary for the Du Pont role. “I was treated differently when I looked like that. It wasn’t anything we anticipated. Once I arrived on set, people kept a distance from me. I think that, in a way, paralleled how Du Pont felt in life, so it was a good thing.”

This, apparently, extended to a remoteness from his co-stars Channing Tatum and Mark Ruffalo. “I didn’t get to know Mark or Channing very well while we were shooting. It wasn’t anything planned, we just naturally didn’t interact, aside from the scenes we were doing. We didn’t hang out, or bond.”

However Carell takes fright at any suggestion he may be getting into method acting – “I’m so hesitant to talk about that, because it sounds so pretentious” – preferring instead to heap more praise on Miller. “To be honest, it comes from the director. Bennett set a tone that the film wasn’t going to be glib.” It also seems to have helped that both the real-life Mark Schultz and Dave’s wife, Nancy, turned up to watch the filming: “That added a responsibility and a weight to what we were doing. I think we all felt the impetus to take it seriously.”

Facebook Twitter Pinterest Carell with Mark Ruffalo in Foxcatcher. Photograph: Sony Pictures/Courtesy Eve/R

All of which is a far cry, of course, from the competitive chuckleheadedness of Anchorman; he rolled on to the sequel straight after finishing Foxcatcher. “God, it could not have been more different. There was no levity at all when we were shooting Foxcatcher. Anchorman 2 was nothing but silly.” It begs the question: how did he manage it? Wasn’t there a culture shock? “I try to approach it all in the same way. I don’t think a character knows they are in a comedy or a drama. If Du Pont’s life hadn’t ended the way it did, it could be an absurdist comedy: a millionaire who likes wrestling.”

Yes, but Carell is far from the first comic who has headed over to the serious side of town – and more than one has ended up losing the funny. Is he concerned? “Not really. To me, they are different styles of entertainment, with different methods.

“I’ve never cared about being taken seriously – I just see myself as an actor. Most of my career, I’ve just taken what I’ve been offered. I always feel most comfortable as part of a ensemble. Whether it’s a comedy or a drama, I like to fit in. It’s best not to stick out.”

By now, I’m thinking Carell is a most cautious film star. Perhaps the clue to it all comes via a throwaway line as it gets close to chucking-out time. Discussing his near-ubiquity since he hit the big time with The 40-Year-Old Virgin and the US version of The Office in 2005, Carell suddenly turns hard. “You know, that didn’t happen till I was 40. All of that came to pass after I had a long career as an actor. It sounds such an aw-shucks kind of thing to say, but I just wanted to make a living. That was the goal: to be able to have a family and support them.”

All the carapace of professionalism, the studious responses, the thoroughly non-anarchic kidding around make a lot more sense if you consider what must have been a 20-year hack through the lower reaches of the improv comedy circuit, the painful process of guest-actor auditions and down-the-bill status jockeying. Carell has always been a bit of a poster boy for the joys of family life, but his stories about the impact of parenthood become intensely resonant. He launches into a well-rehearsed anecdote about trying out for a Julia Louis-Dreyfus sitcom called Watching Ellie shortly after the birth of his daughter. For him, the point is that fatherhood made him “relaxed”, and he ended up nailing it. But his analysis is telling: “For so long, the struggle was the career. The aim and goal was how to get the part, how to audition better, how to get ahead.”

For once, I don’t feel sceptical when Carell says he feels “very thankful to be part of a movie like this” and “even more thankful for the success” he’s had in general. Hollywood cliches they may be, but in the decade or so since The 40-Year-Old Virgin, Carell has defied all expectations – his, as well as ours – to find himself inching closer to the very top of the tree. An Oscar nomination may or may not be waiting for him in the next fortnight, but he remains admirably phlegmatic about his future acting prospects. “You always strive to be part of something decent, or even good. That’s the hope. But I don’t have a masterplan; I never did. The worst thing that could happen is that you’re terrible. And you learn from that.”

• Foxcatcher is released in the UK on 9 January