The 21-year-old model just landed the role in David Fincher's "Gone Girl," playing opposite Ben Affleck's Nick Dunne as his college-age mistress.
"So happy to announce my casting in David Fincher's 'Gone Girl' opposite Ben Affleck!!!" she posted to her Instagram account Monday.
Ratajkowski joins Rosamund Pike, who will play Nick Dunne's wife Amy, and Neil Patrick Harris and Tyler Perry have reportedly snagged roles in the film, based on the Gillian Flynn bestseller.
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