Joaquin Phoenix's laugh in "Joker" is considered one of the most compelling cinematic moments. The 49-year-old won an Oscar for his role in Todd Phillips' 2019 drama, which has since gone down as a landmark piece of cinema.

Phoenix returns to the role in 2024's Joker: Folie à Deux, which also introduces Lady Gaga as Arthur's admirer and fellow Arkham inmate Harleen "Lee" Quinzel. The sequel is also a musical, offering a stylized look at what happens when Arthur fights for his freedom and finds love in a city still obsessed with the Joker.

Lady Gaga and Joaquin Phoenix were among the stars on had for the Joker: Folie a Deux premiere in Los Angeles Monday evening.