Anne Desbarèdes is a young woman who is married to a wealthy businessman and lives a monotonous existence in the small commune town of Blaye. After indirectly witnessing a murder in a café, she returns to the scene of the crime the next day and meets Chauvin, who informs her in more detail about the events that took place. Mentally unbalanced, Anne begins to believe that Chauvin intends to kill her.