Production is underway for Todd Philips' Joker: Folie à Deux, and fans have been getting their first glimpses of Lady Gaga and Joaquin Phoenix as Harley Quinn and The Joker. Several on-set photos have already been spread, but something different has surfaced.Joker: Folie à Deux is the sequel to the 2019 movie Joker, also written and directed by Philips and starred Phoenix as Arthur Fleck/Joker. Joker functioned as an origin story, mainly focusing on Arthur's life leading to his transformation into the Clown Prince of Crime. In contrast, the sequel will start with Arthur fully transformed and will most likely feature him only as Joker. Another departure from the first movie has had fans abuzz since its announcement - Joker: Folie à Deux is a musical. While it's unclear how much singing Phoenix will do as Joker, Harley Quinn will certainly be breaking into song throughout the movie since she's played by Lady Gaga, whose music career precedes her acting career.RELATED: Brendan Gleeson Joins Joker 2 With Joaquin Phoenix And Lady GagaFans curious about what Lady Gaga's Harley Quinn will sound like may have an answer. A video posted on Twitter by Joker Folie News features audio of Lady Gaga singing. Although Lady Gaga doesn't physically appear in the video, it is unmistakably her voice. Due to the video's quality, the song is difficult to identify; whether it's a cover of a song or an original piece written for the movie is unclear. What is clear is that Lady Gaga is already hard at work lending her voice to Joker: Folie à Deux.

Joker: Folie à Deux details are sparse, but fans have gotten a few crumbs of information thus far. On top of photos of Lady Gaga and Phoenix in their makeup and costumes, fans have also seen pictures suggesting Harvey Dent - and, therefore, Batman villain Two-Face - might appear in the movie. So far, it's been confirmed that Zazie Beetz will reprise her role from the first movie and that Brendan Gleeson, Catherine Keener, Jacob Lofland, and Harry Lawty have joined the cast. Gleeson, Keener, Lofland, and Lawty's roles have not yet been revealed. DC Studios co-head and co-CEO James Gunn has also confirmed that neither Joker nor Joker: Folie à Deux are canon in the DCU's continuity but fall under the DC Elseworlds umbrella - stories that aren't part of canon continuity but allow filmmakers to bring their unique and sometimes more mature vision to DC's characters.

Fans who have watched the video of Lady Gaga singing are speculating that she is singing from within Arkham Asylum, Gotham's notorious villain-filled prison. If that's the case, it begs the question: is Joker still in Arkham at the beginning of the movie? Is the song Lady Gaga is singing in the video what will be playing as Harley and Joker escape from Arkham? Whether the song is an original or a cover, a solo for Harley or a duet between her and Joker, it's undoubtedly not the last hint at Joker: Folie à Deux's musical elements that fans will get before the movie's release.

Joker: Folie à Deux will premiere in theaters on October 4, 2024.

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Source: Joker Folie News on Twitter