3. Colin Sullivan - The Departed
Matt Damon is a natural for playing a good guy, so it's rare that he ever takes the villain role, though as State Police Officer Colin Sullivan, he totally knocked it out of the park in Martin Scorsese's Best Picture-winning crime drama. Sullivan is a corrupt cop trying to help his crime boss pal Frank Costello (Jack Nicholson) smoke a rat out of his crew, using his considerable resources to do so. The result is a brilliantly sniveling performance from Damon, one which sees the actor at easily his most unlikable, as the net draws ever-closer on undercover cop Billy Costigan (Leonardo DiCaprio). In a film packed with brilliant performances, Damon is certainly one of the stand-outs, his greatest moment being when Costigan takes him hostage and threatens to kill him, resulting in him breaking down into a pathetic, sobbing mess, moments before...well, those who've seen it know what's coming...And though the ending was changed from the original climax in Infernal Affairs, Damon shoots it through perfectly (pun intended).