Veterinarian Serge (François Cluzet) and his wife, Elisabeth (Brigitte Roüan), have two children, Olivier (Emmanuel Morozof) and Nadine (Faye Gatteau), but Olivier is the obvious favorite. Even Nadine is under his spell. So when Olivier goes missing, it's small wonder that the rest of the family collapses. Elisabeth retreats into psychosis, and Serge accepts a job abroad. Years later, a Paris street hustler suffering from memory loss is identified as Olivier, but not everyone is convinced.