Betty Fisher (Sandrine Kiberlain) is a successful novelist whose life is struck by tragedy when her only son falls from his bedroom window and later dies in hospital. Sometime later Margot (Nicole Garcia), Betty's mother, sees a young boy playing in the street nearby and brings him home to serve as a replacement son for Betty. The boy's mother, Carole (Mathilde Seigner), then reports the disappearance to the police, helping to set off a chain of events which bind the protagonists together in ways they never expected. Adapted from a novel by Ruth Rendell.