WARNING: The following article contains spoilers for director Todd Phillips' Joker, in theaters now.
Joker stands out among most comic book-inspired filmsby existing more as a singular project rather than one that slots into an overarching cinematic universe. Played by Joaquin Phoenix, Arthur Fleck spends the film slowly unraveling while everything he thought he knew about his life turns out to be a lie, or at least far more complicated than he previously believed. Slowly going off the deep end, he embraces the identity of the Joker, a title he received without anyone knowing he inspired Gotham City's lower class by killing three yuppie employees of Wayne Enterprises.
However, that doesn't mean the film is entirely self-contained; the doors are slightly open for a potential follow-up. In fact, Joker quietly sets up a darker examination and origin of not only the Joker but also Batman.
Here's how the ending of Joker plays out, and potentially lays the foundation for an even grimmer Gotham than almost any we've previously seen.
After making fun of Fleck's poorly received stand-up routine on national television, talk show host Murray Franklin (Robert De Niro) decides to bring the struggling comedian on as a guest. What he isn't aware of is that Fleck has gone off the rails. Revelations about his parentage have left him shaken, with Fleck unsure whether billionaire Thomas Wayne (Brett Cullen) -- yes, that Thomas Wayne -- is his birth father, or whether Penny (Frances Conroy) is truly his mother.
By the time Fleck arrives to appear on the show, he has already killed his mother, as well as one of his former co-workers. He practices his Joker routine multiple times, seemingly intending to pull out a gun and kill himself on live television as the punch line of a knock-knock joke.
When he takes the stage, he's actually able to muster some polite laughter from the studio audience. Introduced as the Joker, Fleck reveals in the increasingly heated interview that he was the one who killed three Wayne Enterprise employees, and pushed the city into chaos. Franklin becomes angry with his rationalization, provoking Fleck until he pulls out his gun and shoots the host in the head. The audience cowers or flees, while Fleck fires a few more shots into Franklin before he's arrested.
Fleck never reaches police headquarters, however. Instead, riots break out across Gotham, and squad car transporting Fleck is sideswiped by an ambulance carrying people wearing Joker masks in tribute to him. An unconscious Fleck is pulled from the wreckage, and by the time he comes to, he's surrounded by cheering people in makeshift Joker costumes. It's a triumphant moment for Fleck, who creates a bloody smile across his face and moves for the crowd, but is again apprehended by police.
By the end of the film, the chaos has at least been somewhat contained, and Fleck has been sent to a mental facility. But there are many people in Gotham left dead, including Thomas and Martha Wayne, who are both shot in an alley in front of their young son, Bruce (Dante Pereira-Olson). The film ends with Fleck chased by an orderly after, it's implied, he murders his new social worker and tries to escape the hospital.
Joker doesn't leave much room for a sequel, but it does create a version of Gotham that will inevitably transform into a setting more recognizable to comic book fans. The Joker has inspired an entire city to give in to its dark side and embrace outright chaos. It's still unclear who Arthur Fleck really is, besides a murderer. It's a morally tricky ending, with the question remaining whether Fleck was justified in his actions, at least to himself. He's finally at peace, something that previously eluded him. He's earned the victory he sought, and the city is a worse place for it.
It's not inconceivable that Batman could eventually confront this version of the Joker, but it's unlikely. The age difference between the pair would make it near impossible for Fleck to offer much of a fight to this world's Batman, who presumably wouldn't be active for another decade or so. If anything, Joker's actions could become a major part of Bruce's inspiration to become the Dark Knight, especially if he were to remember his first meeting with Fleck earlier in the film. But this could in turn also inspire any number of people to assume the Joker role themselves.
Directed by Todd Phillips, Joker stars Joaquin Phoenix, Robert De Niro, Zazie Beetz, Bill Camp, Frances Conroy, Brett Cullen, Glenn Fleshler, Douglas Hodge, Marc Maron, Josh Pais and Shea Whigham.