Bradley Cooper (right) plays Chris Kyle in American Sniper. The film has become a cultural phenomenon and has spawned knee-jerk squabbling. Courtesy of Warner Bros. Pictures hide caption

itoggle caption Courtesy of Warner Bros. Pictures

Antoine-Olivier Pilon plays 15-year-old Steve in Xavier Dolan's Mommy. Shayne Laverdière/Roadside Attractions hide caption

itoggle caption Shayne Laverdière/Roadside Attractions

The documentary Red Army profiles Viacheslav "Slava" Fetisov — one of the most decorated athletes in Soviet history. Slava Fetisov/Slava Fetisov/Sony Pictures Classics hide caption

itoggle caption Slava Fetisov/Slava Fetisov/Sony Pictures Classics

The Imitation Game, starring Keira Knightley and Benedict Cumberbatch, follows the story of mathematician Alan Turing — from his efforts to break Germany's Enigma code during World War II to his conviction for homosexuality. Jack English/Courtesy of Black Bear Films hide caption

itoggle caption Jack English/Courtesy of Black Bear Films

David Oyelowo portrays Rev. Martin Luther King Jr. in Selma. He says his experience growing up in Nigeria, without experiencing being a minority, helped him approach the job of playing such an iconic figure with less baggage than an American actor might. Atsushi Nishijima/Paramount Pictures/AP hide caption

itoggle caption Atsushi Nishijima/Paramount Pictures/AP