Director Todd Phillips officially confirmed that a sequel to Warner Bros.'s Joker is moving forward.

In a series of photos shared on Instagram, Phillips revealed not only the working title for the sequel to the original 2019 film -- Joker: Folie à Deux -- but that Joaquin Phoenix is already reading the script. Written by Phillips and Scott Silver, Joker: Folie à Deux does not have a release date. In terms of the working title, Folie à deux is a phenomenon in which two or more individuals, typically family members, experience an identical or similar mental disorder.

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News of a Joker sequel comes after reports that greenlighting a sequel 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.

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."

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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."

News of a Joker sequel also comes after reports that Zaslav had reached out to Phillips in the hopes that the director would take on the responsibility of "advisor" for DC Films. However, according to inside sources, while Zaslav and Phillips have a "rapport," Phillips is "not an expert" on the DC Universe. Prior to the merger between Warner Bros. and Discovery, it was reported that Zaslav was seeking "someone to serve as a creative and strategic czar similar to what Marvel has in Kevin Feige."

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

Source: Instagram