After a chaotic night of rioting in a marginal suburb of Paris, three young friends, Vinz, Hubert and Saïd, wander around unoccupied waiting for news about the state of health of a mutual friend who has been seriously injured when confronting the police.

A second-class horror movie has to be shown at Cannes Film Festival, but, before each screening, the projectionist is killed by a mysterious fellow, with hammer and sickle, just as it happens in the film to be shown.