Mr Duval, a country vet and his wife, live deep in provincial France. Their two children are 9 year old Olivier, the apple of his mother's eye and his older sister Nadine. Mrs Duval sends Olivier to deliver food to her ailing mother in law. The child goes missing and the loss breaks up the already fragile family in a mass of recriminations, Mr Duval taking a post in Africa. Six years later the policeman who had unsuccessfully investigated the case, now in the Paris vice squad, comes across a teenage rent boy who could be the lost son. The parents take him back unquestioningly lavishing presents upon him much to the alienation of Sister Nadine, for whom, Olivier's attention now is definitely sexual.