Lady Gaga; Joaquin Phoenix.Photo: Eamonn M. McCormack/Getty Images; Steve Granitz/WireImage

Lady Gaga; Joaquin Phoenix

Lady Gagais officially onboard forJoker: Folie à Deux.

The 36-year-old actress and musician is set to star alongsideJoaquin Phoenixin the upcoming musical sequel to 2019’sJoker.

Gaga confirmed her casting on social media Thursday, postingan animated videoof her and Phoenix’s silhouettes set to old-timey music.

Along with the title, she shared the film’s release date: Oct. 4, 2024.

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PEOPLEconfirmed Gaga’s involvementin the film — specifically, that she was in talks to play Harley Quinn — back in June.

While plot and character details are still unknown, Harley — originally known as Dr. Harleen Quinzel — is villain Joker’s love interest/sidekick in several iterations of theBatmanstory, and met the sinister prankster while serving as his psychiatrist at Gotham City’s Arkham Asylum.

The film will seeTodd Phillips(The Hangover) return as director, as well as co-writer alongside Scott Silver.

RELATED VIDEO:JokerBreaks October Box-Office Record with $93.5 Million

Phillips, 51, alluded in June that a sequel toJoker— whichbroke box-office recordsas the first R-rated movie to hit the $1 billion mark in 2019 andearned 12 Oscar nominations, including aBest Actor winfor Phoenix — was in pre-production on Instagram.

The two-part post opened with the red cover ofa script titledJoker: Folie à Deux. The binder was dated May 18 and featured his name next to that of Silver, 57, with whom he also co-wrote the firstJokerscreenplay.

Asecond shot showedPhoenix, 47, casuallyreading the script on a couchwhile smoking a cigarette.

source: people.com