Robert Pattinson, who was cast in the film in January, revealed Morton's casting in an interview with MTV.
"I know Juliette Binoche is in it now, and Samantha Morton. It's going to be a crazy cast. Like, I have a feeling it's going to be amazing," Pattinson said.
David Cronenberg is directing the film, which is based on the classic Don DeLillo novel.
Paul Giamatti is also starring in the movie, which follows a young billionaire (Pattinson) through a wild 24 hours of his life in which he loses his fortune.
Marion Cotillard was previously attached to star in the film, but she was forced to leave the project due to her recently announced pregnancy.
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