20 Behind-the-Scenes Secrets from The Dark Knight
Heath Ledger Didn’t Remain in Character
It would be easy to assume that, because Heath Ledger’s depiction of the Joker is so intense, and he did a lot of method acting to play the character, he may have stayed in character even when cameras weren’t rolling. That would have been incredibly scary for other members of the cast, in part because the Joker isn’t someone you want to have to give directions to.
Although Heath did use method acting, he didn’t stay in character when they weren’t filming. Instead, he would joke around with the rest of the crew, and take smoke breaks. He was a normal actor who just happened to have green hair and lots of white makeup on his face.