Veteran actor Brett Cullen has been cast as Batman’s father Thomas Wayne in the upcoming Warner Bros. “Joker” film, an individual with knowledge of the project tells TheWrap.

Cullen replaces Alec Baldwin who had to drop out due to a scheduling conflict.

The film, set to be directed by Todd Phillips, will star Joaquin Phoenix as the clown prince of crime.

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Thomas Wayne first made his appearance in Detective Comics #33 (Nov. 1939) in Batman’s origin story. He is the father of Bruce Wayne — who is Batman — husband of Martha Wayne and was a gifted physician and philanthropist in Gotham City. When Dr. Wayne and his wife are murdered in a street robbery after a screening of Tyrone Power’s “Zorro,” the young Bruce Wayne becomes inspired to fight crime as the vigilante Batman.

While story details are being kept under wraps, TheWrap previously reported that the origin story for Batman’s nemesis will be more of a mid-budget crime thriller than a superhero blockbuster.

The film is being produced by Phillips and Bradley Cooper under their Joint Effort banner, and Emma Tillinger Koskoff. It is executive produced by Richard Baratta, Michael Uslan, Joseph Garner and Bruce Berman.” The film will be released on Oct. 4, 2019, with production set to begin in New York in September.

Robert De Niro, Zazie Beetz, Marc Maron and Frances Conroy — as the Joker’s mother — round out the rest of the cast.

Cullen is repped is by Domain Talent.

Comicbook.com first reported the news.