After a three-month shoot, filmmaker Todd Phillips has confirmed principal photography on next year's Joker solo film has been completed, with the DC Comics movie moving into post-production.

Phillips, who directs and co-wrote the upcoming film, shared a photo of himself from the movie set on his Instagram page. In what appears to be a mental hospital, the Hangover filmmaker revealed that the movie has now entered the lengthy editing phase to prepare it for its October release.

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The post confirms reports from the beginning of the month that film wrapped principal photography in Brooklyn with Joaquin Phoenix and Zasie Beetz both seen in costume taking publicity photos in the film. On the final day of filming, Phoenix was seen dressed as both the Clown Prince of Crime and in his civilian identity as Arthur Fleck.

With the film now officially in post-production, a first look trailer is likely to be in the works to debut sometime early next year.

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Directed and co-written by Todd Phillips, Joker stars Joaquin Phoenix as the titular character along with Robert De Niro, Marc Maron, Zazie Beetz, Frances Conroy, Brett Cullen and Bill Camp. It is scheduled to be released on October 4, 2019.