Joker 2 will reportedly feature Harley Quinn, possibly played by Lady Gaga – but why isn’t Margot Robbie playing Harley Quinn in Joker 2, if she plays the current version of the character in the DC Extended Universe? The DC Universe has gone through various changes in recent years, branching out to different universes in film and TV. The most popular branch in the DC Universe is the DCEU, which has brought some of the most popular and beloved characters from DC Comics to the big screen, among those the Joker and Harley Quinn.

The DCEU’s Joker (Jared Leto) and Harley Quinn (Margot Robbie) made their debut in David Ayer’s Suicide Squad, but only Harley Quinn returned for more adventures. Although Leto’s Joker appeared in Zack Snyder’s Justice League, since her debut in Suicide Squad Harley Quinn has led her own movie in Birds of Prey and joined a new Task Force X team in James Gunn’s The Suicide Squad. Meanwhile, in a different part of the DC Universe, a darker, more grounded version of the Joker arrived in Todd Phillips’ Joker, set in a separate universe from the DCEU and with Joaquin Phoenix playing a new version of the Clown Prince of Crime named Arthur Fleck.

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Joker was quite divisive among critics and it drew a lot of backlash even before its release, but it ended up being a huge box office success and was nominated for different awards, proving that there is interest in this darker version of the character. After a lot of rumors about a sequel, Joker 2 was confirmed to be in development in June 2022 when Phillips shared a pic of the finished script (titled Folie à Deux) and Phoenix reading it. Not long after, news broke about Joker 2 being a musical and featuring Harley Quinn, with Lady Gaga in talks to play the role. Of course, this raised questions about why Margot Robbie isn’t playing Harley Quinn in Joker 2, and it’s all because these are two different universes.

Joaquin Phoenix as Joker and Lady Gaga

The DCEU hasn't had the expected success since its beginning in 2013 with Man of Steel, and the underperformance of movies like Suicide Squad and Justice League led Warner Bros. to change its plan for the DC Universe, which included exploring universes separate from it. As a result, movies like Joker and The Batman are set in different universes away from the DCEU, which is why the DCEU can have Ben Affleck and Michael Keaton as Batman while Robert Pattinson plays a different version, and Jared Leto can play the Joker while Joaquin Phoenix also does so, meaning that Margot Robbie can keep playing Harley Quinn while Lady Gaga (or someone else) also does. Surely, in recent years, there have been actors who have reprised roles across universes, as is the case of J.K. Simmons’ J. Jonah Jameson in Sam Raimi’s Spider-Man movies and now in the Marvel Cinematic Universe, but recasting makes a lot more sense when they are two universes with a different tone and time setting.

Joker is a lot darker than the movies where Margot Robbie has played Harley Quinn, in which she has been free to explore the character’s sense of humor, but Joker went on a much more serious route, which doesn’t have the vibe of a comic book movie. In addition to that, Joker was set many years before Margot Robbie’s Harleen Quinzel became Harley Quinn, so it makes sense that she won’t play the role in Joker 2, instead leaving the spot open for another actress and a completely different interpretation of Harley Quinn. It’s to be seen what Harley Quinn’s role in Joker 2 will be, as she could be Arthur’s love interest, sidekick, or even a copycat, thus why the working title Folie à Deux.

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