Kristen Stewart's Ex Romances Uma Thurman in New Flick

Undercover lovers!

In this spring's Ceremony, Kristen Stewart's indie actor ex-boyfriend, Michael Angarano, has his sights set on a much-older woman: Uma Thurman.

As Sam Davis, Angarano, 23, tries to thwart the impending nuptials of a famous documentary filmmaker (Lee Pace) after he becomes infatuated with his fiancee (Thurman, 40).

"It was a lot of fun to play a character who is kind of reckless in how he chooses to treat people," Angarano has said of his role opposite Thurman. "I can't talk about this movie without saying how cathartic an experience it is."

Check out the trailer for Ceremony -- directed by Henry Winkler's son, Max! -- above before the film hits theaters April 8.