Lady Gaga may appear in Warner Bros.'s upcoming Joker sequel.

According to The Hollywood Reporter, musician and actor Lady Gaga is currently in very early talks to appear in director Todd Phillips' Joker sequel as Harley Quinn, opposite Joaquin Phoenix. However, sources report that Warner Bros. and Phoeniz have yet to close a deal on the actor's return for the sequel which is also reportedly being planned as a musical.

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Phillips officially confirmed that a follow-up to 2019's Joker would be moving forward under the working title Joker: Folie à deux, named for a phenomenon in which two or more individuals, typically family members, experience an identical or similar mental disorder. Though Phoenix has not officially signed onto the film, Phillips did share a photo of the actor reading the script, which was written by Phillips and Scott Silver.

News of a Joker sequel came after reports that greenlighting a follow-up to Joker was a priority for the new Warner Bros. Discovery CEO David Zaslav. When it was released in theaters in 2019, Joker grossed over $1 billion at the worldwide box office, making it the highest-grossing DC film ever. Meant to serve as an origin story to the infamous Batman villain, Joker is set in a self-contained universe meant to be entirely separate from films like Zack Snyder's Justice League and Matt Reeves' The Batman.

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In a 2019 interview, Phillips said that he was open to a Joker sequel, despite his intention that the original film be an open-and-shut story. "When a movie does $1 billion and cost $60 million to make, of course it comes up," said Phillips. "But Joaquin and I haven’t really decided on it. We’re open. I mean, I’d love to work with him on anything, quite frankly. So who knows? But it would have to have a real thematic resonance the way this one did, ultimately being about childhood trauma and the lack of love, and the loss of empathy."

Though Phoenix, who portrayed Arthur Fleck/Joker in the film, is currently reading the sequel's script, he has previously expressed doubts about the possibility of a Joker follow-up. "There are some things we could do with this guy and could [explore] further," he said. "But as to whether we actually will? I don’t know."

Joker: Folie à Deux does not have a release date.

Source: The Hollywood Reporter