In the Gorges du Verdon, Major Thierry Rouvier, close to retirement, and young Captain Elie Zakine are brought together to investigate the murder of a 78-year-old man found on the Castillon dam. They are soon joined by Chloé Delage, a psycho-criminologist who is none other than Major Rouvier's daughter. Chance doesn't necessarily make things right, as she and Thierry have a complicated family relationship.