Joker: Folie Deux is a 2024 American musical psychological thriller by Warner Bros. It's the long-awaited sequel to 2019's Joker, directed by Todd Phillips, and it sees Joaquin Phoenix reprise the role of Arthur Fleck (aka Joker). It also stars Lady Gaga, who plays his love interest Harley Quinn, with Brendan Gleeson, Catherine Keener and Steve Coogan also joining the cast.