Heath Ledger was an Australian actor born in 1979 who gained fame for his roles in 10 Things I Hate About You and Batman's The Dark Knight, where he played the Joker. Some said he became obsessed with the role of the Joker, locking himself away for weeks to fully immerse himself. He died unexpectedly in 2008 at age 28 from an accidental prescription drug overdose. After his death, fellow actors Johnny Depp, Colin Farrell, and Jude Law donated their salaries from an unfinished film to Ledger's young daughter to provide for her future.