Part of Gone Too Soon featuring Chadwick Boseman and River Phoenix, and The Dark Knight with Christian Bale and Gary Oldman.
Nobody remembers the charming lead from 10 Things I Hate About You, and that was always the problem with Heath Ledger until Brokeback Mountain (2005) proved he could carry a serious film. That Oscar nomination changed the conversation, but it didn't define him. What defined him was six weeks alone in a London hotel room, filling a journal with Clockwork Orange stills, hyena photos, and the word 'chaos' highlighted in green. The Joker that came out of that experiment is what people mean when they say his name. The Dark Knight released in July 2008, six months after he died.
The Dark Knight made over $1 billion at the box office and Ledger's Joker is the reason it holds up. The posthumous Oscar came with a particular cruelty: the Academy announced his nomination on January 22, 2009, the one-year anniversary of his death. His daughter Matilda Rose owns the Oscar. He became the second actor ever to win posthumously, the first from a comic-book film. Every Joker since lives in his shadow.
He sought the Joker role himself, pushing for the part after seeing Batman Begins. Less noticed: he was a chess obsessive who played strangers at Washington Square Park in Manhattan, and a compulsive photographer who painted over his shots with nail polish and markers. The performance left every successor in an impossible position.
Production on The Imaginarium of Doctor Parnassus halted immediately at his death. Director Terry Gilliam recruited Johnny Depp, Jude Law, and Colin Farrell to finish his remaining scenes. The film released in 2009 and closed with the credit 'A Film From Heath Ledger & His Friends.' His parents and sister accepted his posthumous Best Supporting Actor Oscar at the February 2009 ceremony.