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Joker started production last week, and Warner Bros. just issued a press release announcing that news along with the main cast and crew.

The press release confirms that Joaquin Phoenix will play Arthur Fleck, confirming a report from over the summer about his pre-Joker real name. Robert De Niro has received top billing and will reportedly play a talk show host that plays a role in Arthur Fleck’s transformation into the Joker.

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