Three blokes,claiming that their car is broken-down,burst into an isolated house in the Alpilles where Roger and Irène take care of maladjusted teenagers.One of the intruders,Pierrot ,is wounded.In this place ,there are two clans.One of the adolescents ,Micou , fixes the car and takes advantage of the opportunity to try to slip away .Unmasking himself ,the gangster shoots on the car and stops him.Now they all realize that they are held hostages.