In 2019's Joker, the titular Clown Prince of Crime discovered his life was not a tragedy — "it's a f**king comedy!" Now, Joaquin Phoenix's Arthur Fleck is back, and this time around, life is a musical.

Joker: Folie à Deux — that is, "madness for two" — picks up with Arthur Fleck at Arkham Asylum, where he will meet Oscar winner Lady Gaga's Harleen Quinzel, aka Harley Quinn, his psychiatrist-turned-partner in crime. Like the first film, Folie à Deux hails from Oscar-nominated director Todd Phillips from a script that he co-wrote with Oscar-nominated writer Scott Silver.

Reprising her Joker role alongside Phoenix is Zazie Beetz as single mother Sophie Dumond. New additions to the cast include Oscar nominees Brendan Gleeson, Catherine Keener and Steve Coogan, plus Harry Lawtey, Ken Leung, and Jacob Lofland.

Joker holds the distinction of being the most Oscar-nominated comic book movie of all time with 11 total nominations, including Best Picture, Best Directing and Best Adapted Screenplay. At the 92nd Oscars, Phoenix won Best Actor in a Leading Role for his performance as the Joker, while composer Hildur Guðnadóttir took home Best Original Score.

Guðnadóttir is back as the composer on Folie à Deux, which has largely reassembled Phillips' creative team from the first film: Oscar-nominated cinematographer Lawrence Sher, Oscar-nominated film editor Jeff Groth, Oscar-nominated hair and makeup designers Kay Georgiou and Nicki Ledermann, and production designer Mark Friedberg. The producers are Phillips, Oscar nominee Emma Tillinger Koskoff, and Joseph Garner.

Joker: Folie à Deux dances into theaters on Oct. 4. Watch the teaser trailer below.

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