The two-minute short film, which debuts on April 6 in the UK, depicts Knightley acting in a scene where her boyfriend attacks her. After the first hit, Knightley breaks character and looks at the camera, saying, "Sorry, we didn't agree to that," referring to the sudden strike to her face.
The violence continues and intensifies, as the actress is thrown to the floor and repeatedly kicked, as the words, "Domestic violence - isn't it time someone called cut?" appear on the screen.
"I wanted to take part in this advert for Women's Aid because while domestic violence exists in every section of society we rarely hear about it," Knightley said in a statement. "We may not think we know someone who has experienced domestic violence, but this does not mean that it is not happening."
Knightley and director Wright reportedly donated their time for free to make the PSA.
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