Retna Digital

Keira Knightley is brutally attacked by her boyfriend in a shocking new domestic violence ad for the charity Women's Aid.

The two-minute clip, which debuts April 6 in movie theaters, opens with the actress, 24, heading home from a long day of filming.

When she gets home, her boyfriend verbally and physically attacks her because he thinks she's having an affair with a costar.

As the camera pans out, Knightley lays on the floor as the beating continues. The location is revealed to be an empty film set.

"Isn't it time someone called cut?" the ad says.

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Atonement director Joe Wright directed the spot, which Knightley says she volunteered to do because "while domestic violence exists in every section of society we rarely hear about it."

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Adds the actress, "Domestic violence affects one in four women at some point in their lifetime and kills two women every week."