While there have been plenty of great Batman movies over the years, none have received the almost universal acclaim that Christopher Nolan's The Dark Knight did when it was released. The film was praised for everything from its score to its cinematography, direction, and screenplay — and who can argue? But what really makes The Dark Knight are the performances, especially those by the film's leads. But although Christian Bale wowed audiences as the Caped Crusader in Batman Begins, the actor felt as if one of his co-stars kept him from true greatness with the sequel. Would you be surprised if we told you that the co-star was Heath Ledger?