When Catherine (Nathalie Baye) is caught with her illicit lover by her father-in-law Paul (Michel Serrault), the concerned father leaves to tell his son Thomas (Francois Dunoyer) about the incident. Paul is injured in an auto accident and returns home in a wheelchair unable to speak. Catherine’s guilt weighs heavily on her as she hopes to never let Thomas know she was unfaithful. She panics and seeks a way to eliminate Paul in this psychological thriller.