PEOPLE's review calls him "fearless" as the Joker and notes that his role "helps make The Dark Knight unforgettable." And with a record-breaking $158.3 million take at the box office this weekend, the film – and Ledger's role in it – have become a part of movie history.
Just how powerful was his performance? Said his costar Michael Caine earlier this month: "I think Heath will surely get a posthumous nomination for an Academy Award."
Tell us: How do you think Heath Ledger might fare come Hollywood's awards season?