One of the reasons audiences were so intrigued by Joker in 2019 is because there was room to interpret the film as you saw fit. Some theorized that the whole final act of the film played out in the mind of its titular character, while others believed he'd become the Clown Prince of Gotham.
This is the sort of ambiguity that a single film can allow. Unfortunately, by continuing the story, one has to provide concrete answers. Joker: Folie à Deux not only provides these answers, but takes a closer look at why the events of the first film took place at all. It's a critique and a continuation all in one. But how does this film end? Is there more ambiguity? Perhaps a tease of more films to come?
SPOILERS for Joker: Folie à Deux ahead
Joker: Folie à Deux ends in tragedy. After a lengthy court case, Arthur Fleck (Joaquin Phoenix), the man who has become Joker, is stabbed in a holding cell. The film concludes with Arthur bleeding to death on the floor, while the man who stabbed him proceeds to cut a smile into his face.
The implication, of course, being that this man will decide to take up the mantle of Joker, and that Arthur's life will only be a small part of the idea of the Joker. The chaos he wrought, and the imagery he conjured, will last far longer than his memory. It's sad and poetic, but it also slams the door shut on any possibility for a conventional sequel.
There are some ideas that go unexplored in Joker: Folie à Deux, like the fate of Harvey Dent (Harry Lawtey), who gets injured in a car bombing but never officially becomes Two Face on screen. Then there's the scene in which Harley Quinn (Lady Gaga) claims to be pregnant with Arthur's child.
Todd Phillips has stated that he's done with the series
There's a world in which DC could extend one of those storylines out in a spinoff or a legacy sequel. That said, director Todd Phillips and star Joaquin Phoenix are done. The two men have stated over and over again that they poured all of their ideas into the second film, and have nothing left for part three.
"It’s not really where this movie is headed for me," Phillips told The Hollywood Reporter. "I feel like my time in the DC Universe was these two films." Given that the critical and commercial reception to the second Joker film is seemingly less, um stellar, than the first, we can't imagine DC would try to get more out of this franchise. The rare two and done.