Heath Ledger passed away before he could reap the rewards of the painstaking method acting he put himself through preparing to play The Joker in 2008's The Dark Knight. He was posthumously awarded the Academy Award for best supporting actor. The Australian threw himself into the mindset of DC's Clown Prince entirely, shutting himself away with nothing but a journal and his own thoughts. "He pretty well locked himself up in a hotel room for weeks," his father said in the documentary Heath Ledger: Too Young To Die (via the Daily Mail). "He liked to dive into his characters, but this time he really took it up a notch."