Joker: Folie à Deux sees Lady Gaga join the cast in the role of Harley Quinn, the henchwoman to Joaquin Phoenix’s villain.
The film, a follow-up to the 2019 psychological thriller, is due for release on 4 October.
Phoenix reprises his role as the title character, which earned him the Academy Award as best actor in the original film depicting an origin story for the arch enemy of DC Comics’ superhero Batman.
Joker was also Oscar-nominated in the best film category and won for best original score.
The story charted the psychological descent of the film’s protagonist, failed party clown and wannabe comedian Arthur Fleck, and the social forces that transformed him from a dejected loner into a cold-blooded killer who inspires a wave of violence in the fictional metropolis of Gotham City.
Phoenix, known for playing brooding or emotionally troubled characters, was widely acclaimed for one many critics hailed as one of the most chilling and disturbing performances in modern film.
He was the second performer to earn an Academy Award for playing the Joker, following in the footsteps of Heath Ledger, who posthumously won the Oscar for best supporting actor for his 2008 rendition of the character in The Dark Knight.