During her investigation into the murder of a wealthy director of a jewelry store, Samuel Avenberg, Alice finds Mathieu Brémond, with whom she lived a love affair at the faculty. Anton Avenberg, CEO of the jewelry and father of the victim, discovered the body of his son in their mansion. His statements direct the investigation to the trail of a burglary that would have gone wrong. Mathieu, who has become a "hunter" of precious stones on behalf of the victim, is heard as a witness while suspicions fall on Betty Chassard, a young thief who was on the scene at the time of the murder. Alice will discover a world of pretense locked by secrecy and complicated family relationships.