Heath Ledger as The Joker (2008)

When Heath Ledger was cast as the Joker in 2008, fan backlash erupted with online petitions demanding his removal, labeling him an unsuitable choice for the iconic villain. Ledger's posthumous Oscar-winning performance silenced critics, earning him a Best Supporting Actor award and redefining the character for a generation. Ledger's intense method acting, including a legendary diary of psychosis, resulted in a portrayal that 90% of critics now rank as the best on-screen Joker, a vindication unmatched by any other controversial casting.