Seth Rogen has revealed Rihanna left Michael Cera begging for mercy after she slapped him for a scene in new apocalyptic comedy movie This Is The End.
The Unapologetic singer has a cameo in the film which is Knocked Up star Seth's directorial debut, starring James Franco, Jonah Hill, Emma Watson and Michael playing exaggerated versions of themselves as the world begins to end.
In one scene, Superbad star Michael slaps Rihanna on the behind, prompting her to slap him in the face, and Seth told MTV.com the singer did not hold back.
Seth explained: "Rihanna did slap the s*** out of him. For real, he said, 'I'm actually going to slap the s*** out of your a**,' and she was like, 'I'm actually going to slap the s*** out of your face then.'
"We did it like six times, and the last time, he was like, 'I don't think I can do this any more'."
The Mindy Project star revealed he had never met Rihanna before the movie, but after reading she was a fan of some of his previous films he decided to try offering her a cameo.
Seth revealed: "I'd never met her before we made this movie. I read that some of her favourite movies were Superbad and Pineapple Express, and I just remembered it to make me feel good about myself. And then, years later, we were doing this and we were like, who could we get? And I was like, 'Rihanna!'."