In Grey's Anatomy cast news, one of its stars is heading back to the big screen, briefly. Kat Dennings (Nick and Norah's Infinite Playlist),

Woody Harrelson and Grey's Anatomy star Sandra Oh will star in Defendor, according to The Hollywood Reporter.

Peter Stebbings wrote the film in which he will also make his directorial debut. Defendor centers on a regular guy (Harrelson) who believes he has a secret superhero identity.

Dennings will play a teen he befriends, while Sandra Oh is cast as his psychiatrist.

Principal photography begins next month in Toronto.

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