Lady Gaga is officially joining Joker: Folie à Deux as Harley Quinn.

On Instagram, the account for Joker shared a video, which you can see below, confirming Joaquin Phoenix reprising his role as Arthur Fleck alongside Gaga, who will play Quinn. No actual footage from the movie was shown, but it did feature silhouettes of them dancing together.

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Also known as Stefani Germanotta, Lady Gaga first came to prominence as a musician, having sold millions of records worldwide. She's also had a successful acting career, having won a Golden Globe for her role in American Horror Story: Hotel. She also received an Academy Award for Best Original Song for her work on 2018's A Star Is Born. While Lady Gaga did receive an Academy Award nomination for Best Actress for her role in that film, the accolade instead went to Olivia Colman for The Favourite.

Reports Lady Gaga would play Harley Quinn opposite Phoenix cropped up in June. This Instagram video is thus the first official confirmation that she'll actually star in the film. At this time, it's not clear what Lady Gaga's casting means for Margot Robbie, who has played the Clown Princess of Crime in the DC Extended Universe since 2016's Suicide Squad. However, the original Joker film took place separately from the rest of the DCEU, so it seems unlikely to affect her in any major way. That being said, the DCEU has undergone some major shakeups in recent days, with Warner Bros. opting to cancel a nearly-finished Batgirl film.

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Created by Paul Dini and Bruce Timm, Harley Quinn originally debuted in a 1992 episode of Batman: The Animated Series before making her way to the comics. Also known as Harleen Quinzel, Quinn was a psychiatrist at Arkham Asylum that fell in love with the Joker and began helping him in his crimes. The character has changed a lot over the years and has actually broken up with Joker.

At this time, plot details about Joker: Folie à Deux are scarce as the movie is still in the early stages of production. However, there are reports the movie will take place mostly in Arkham Asylum, where Fleck ended up at the end of the 2019 movie. There have also been reports that Folie à Deux will be a musical.

Joker: Folie à Deux hits theaters on Oct. 4, 2024.

Source: Instagram