Sandrine Perrot's investigation takes her from the picturesque fishing towns to the rural hinterland of Brittany's Emerald Coast. Police Lieutenant Sandrine Perrot is on leave from her post in Paris and has settled in Cancale, the oyster capital of Brittany. She is temporarily assigned to the Saint-Malo police station for this case. The body of an unidentified woman is discovered on the Brittany coast path along the bay of Mont- Saint-Michel. With her new assistant, Adel Azarou, she takes on the investigation, which leads them to a cold case from Paris, but also deep into the tragic history of a venerable hotelier family.