In 2019, Phoenix starred as the DC Comics character Joker in Todd Phillips's psychological thriller "Joker"; an alternative origin story for the character. Set in 1981, the film follows Arthur Fleck, a failed clown and stand-up comedian whose descent into insanity and nihilism inspires a violent counter-cultural revolution against the wealthy in a decaying Gotham City. Phoenix lost in preparation, and based his laugh on "videos of people suffering from pathological laughter." Released to critical acclaim at the 76th Venice International Film Festival, the film experienced a polarized critical reception after its theatrical release. While Phoenix's performance received rave reviews, the dark tone, portrayal of mental illness, and handling of violence divided opinions and generated concerns of inspiring real-life violence; the movie theater where the 2012 Aurora, Colorado mass shooting occurred during a screening of "The Dark Knight Rises" refused to show it. Despite this, "Joker" became a box office success grossing over $1 billion (against its $55 million production budget), the first and only R-rated film to do so, becoming Phoenix's highest-grossing film.