Channing Tatum and Steve Carell Tackle Their Darkest Roles To Date

Harrowing true-crime biopic Foxcatcher is already generating Oscar buzz, but it was the film's unconventional casting choices that first made headlines. Funnyman Steve Carell, best known as The Office's bone-headed boss Michael Scott, and Magic Mike star Channing Tatum are tackling arguably their darkest roles to date in the film about an Olympic wrestler and his disturbed multi-millionaire sponsor.

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Carell has had successful dramatic roles in films like Little Miss Sunshine and The Way, Way Back, but even he was surprised at finding himself on the short list to play John Eleuthère du Pont, the paranoid-schizophrenic heir to the du Pont fortune.

"I thought well, why me?" Carell told ET. "This doesn't seem to be a list that I would be on, in terms of playing this character. I was surprised when [director Bennett Miller] called me."

The film is the story of "Team Foxcatcher," the wrestling club at the Olympic training center du Pont built on his family's estate. Channing Tatum and Mark Ruffalo play real-life brothers Mark and David Schultz, Olympic champion wrestlers who become close to du Pont with tragic consequences.

"I just think he was an incredibly lonely guy," Carell said of his character. "And really sad. So I never approached him like he was a villain."

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The film's dark story took its toll on Carell, both mentally and physically. He spent hours in makeup each day to recreate du Pont's high forehead and hawkish nose and adapted his speech to the multi-millionaire's halted cadence, a transformation that be believes ultimately helped him understand his character even better.

"You put on all this make-up and you assume this body language," he told ET. "It's hard to talk about, because you run the risk of sounding really pretentious, but I'd be on set and I'd get the sense that people really didn't want to be around me. So I think that sort of organically had me withdraw, and ultimately it was a good thing for the character."

The ominous mood on set also affected co-star Channing Tatum and his wife, Jenna Dewan, who came to visit the film's set in Pennsylvania.

"My wife was pregnant at the time and she came for like three days," Tatum told ET. "She was supposed to stay for a week, and after the third day she was like, 'I'm going to go home. This isn't any fun at all.'"

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Being isolated from family and friends affected both actors, though they admit that those emotions were key in establishing the film's dark tone.

"It was kind of depressing," Tatum admitted. "It was cold, we were away from our families, it was tough. These were dark people in a dark story to portray."

Foxcatcher premiered at the Cannes Film Festival and is set for release on November 14, 2014.