The Joker and Harley Quinn's relationship in Joker: Folie à Deux could flip one of 2019's Joker's biggest and most unexpected twists. While James Gunn and Peter Safran work on development of the new DC Universe, Todd Phillips will be delivering a follow-up to his smash-hit Joker on October 4, 2024, picking up with Joaquin Phoenix's Arthur Fleck, and introducing Lady Gaga as Harley Quinn. Joker: Folie à Deux's story is expected to focus on the relationship between Fleck's Joker and Quinn, adapting one of DC Comics' most iconic and menacing romance storylines into live-action, though is suspected to also be including as many twists and turns as 2019's Joker.

Joker debuted Joaquin Phoenix's Arthur Fleck, a failed clown and aspiring stand-up comedian who turns to a life of crime and inspires the uprising of a countercultural revolution in Todd Phillips' dark and gritty vision of DC Comics' Gotham City. Throughout the film, Fleck's relationships with his colleagues, his mother, and his neighbors are tested, culminating in his final transformation into the murderous and nihilistic Joker. The ending of Joker saw Fleck institutionalized in Arkham Asylum, which is where 2024's Joker: Folie à Deux is expected to pick up, continuing Joker's twisted reality and unexpected reveals, though one in particular could be completely inverted, revealing more about Fleck's romantic personality.

Joker 2's Harley Quinn Will Likely Invert Arthur Fleck's Big Joker Plot Twist

Arguably Joker's biggest twist came when it was revealed that Arthur Fleck's relationship with his neighbor, Zazie Beetz's Sophie Dumond, was actually a complete fabrication, set entirely in his mind. After their meet-cute in an elevator, audiences watched Fleck and Dumond's romance grow throughout Joker, and the eventual reveal - both to the audience and to Fleck himself - that it had been imaginary aided in pushing Fleck over the edge, completing his transformation into the Joker. Joker: Folie à Deux could invert this twist, if Joker and Harley Quinn's relationship from DC Comics is more accurately depicted, as Fleck could become the one in control.

Typically, Harley Quinn's origin story sees her madly in love with Joker in DC Comics, though the latter strings her along, using her for his own benefit when it becomes necessary to him. If this dynamic is depicted in Joker: Folie à Deux, Arthur Fleck will go from imagining a relationship to feel connection with someone, to actively rejecting affection and toying with a character who adores him. This drastic shift in Phoenix's villainous character could be an interesting story to explore in Joker: Folie à Deux. Of course, Phillips may simply adapt a more mutual romance between the pair, but the dynamic of Joker's love story could still shift dramatically.

Why Harley Quinn's Introduction Is So Important for Joker 2

2019's Joker introduced Arthur Fleck as a man who felt completely alone in the world, neglected by his mother and the love that he'd imagined. Lady Gaga's debut as Harley Quinn in Joker: Folie à Deux means that this storyline won't be repeated, as it would be banal to simply put Fleck through the same character beats from Joker. Introducing a new love-interest who supposedly has a genuine affection for Fleck allows Joker: Folie à Deux to explore new storylines and new relationships. While this will surely lead to plenty of criminal activity, and some distressing moments, a deeper level of connection will be explored in Joker: Folie à Deux.