Brendan Gleeson, who starred in Gangs of New York, will join Lady Gaga, Joaquin Phoenix, and the rest of the ensemble in Joker: Folie à Deux.

In the next Joker sequel from Warner Bros. Discovery, Brendan Gleeson, renowned for a distinguished career that includes parts in Braveheart, 28 Days Later, Gangs of New York, and the Harry Potter series, has been cast.
Joaquin Phoenix reprises his role as The Joker, Batman’s most formidable foe, while Lady Gaga plays Harley Quinn in the movie. There are rumors that it’s a musical.
Joker: Folie à Deux is the first DC movie to have received the green light since Warner Bros and Discovery merged, and it is now shaping up to be a spectacle on par with the first movie, as was just announced.
The announcement that Joker: Folie à Deux will be filmed in Los Angeles and have a $150 million budget, almost three times the budget of the original Joker, was followed by the casting of Brendan Gleeson, whose part in the DC movie is yet unknown.
Along with Joaquin Phoenix, Zazie Beetz is allegedly in discussions to reprise her role in Joker: Folie à Deux. In Joker, Beetz portrayed Sophie Dumond, a neighbor of Phoenix’s Arthur Fleck with whom he fantasized about having a romance.
Brendan Gleeson will next be seen in The Banshees of Inisherin, which will be released in October. Gleeson co-stars in the picture with Colin Farrell and Barry Keoghan, both of whom have just entered the DC world as the Penguin and the Joker, respectively, in The Batman.