Given up for adoption as a toddler, troubled teenager Thomas becomes obsessed with tracking down his birth mother. After years of searching, Thomas finds her single, with a small child, living in a nearby suburb and begins a relationship with her which slowly drives him to an act of madness.

As every year, chief inspector Paul Bellamy spends a few days with his wife Françoise in the family house in Nîmes. Jacques, Paul's stepbrother, turns up unawares, which is bad news since the fellow is an alcoholic good for nothing. Also annoying is this stranger at bay who asks Bellamy for protection. Farewell peaceful holiday!