Agathe likes to describe herself as a mother "like any other". In a charming house, with a talented husband and healthy children, everything seems perfect. However, after 15 years of marriage, the pretty postcard begins to crack... The day a murder is committed in the hotel where her husband was staying for work, an unbearable suspicion sets in... Is the man she shares her life with a murderer? Has she not been trapped in an abusive and toxic relationship for years? What does she really know about Fred? With the emergence of doubt, Agathe plunges into an obsession, and the family unit becomes the arena of a high-tension criminal investigation. Like the fears of our childhood, the monster is no longer in the cupboard, it is in the bed.