In Brittany, a notary is killed with shots to the head; his wife Joséphine is a suspect; her husband had just sold part of their property to two shady real estate developers.

Two shady real estate developers want to buy the Kersaint-Gilly domaine, as well as a fishing boat shed belonging to Cécile Prigent; Cécile refuses to sell, but soon her daughter Gwen is murdered.