Mathilde, a young dancer with a promising career ahead of her, receives a letter from a "chain letter" as she is about to leave on a tour. On the way she reads to her friend Sophie all the disasters that supposedly should befall those who break the chain by not sending someone else the letter. Mathilde finds this funny and isn't worried at all. But on the first stop of her tour, the young dancer falls victim to a series of strange accidents.

Sandrine, a former fashion designer who is unemployed, is now working in a garment factory as a worker. There she meets Mathieu, the company's human resources manager and a former childhood sweetheart. The two of them get closer, but their relationship is hampered by the economic crisis that is catching up with the company... The employees then decide to join forces to buy the company by creating a clothing line, "Les P'tits Lutins", for which Sandrine is, of course, asked to contribute. However, the situation turns out to be tense. How will Mathieu react to these new directions?

Molinat is assigned to the case of a man found with a bullet in his ear on the shore of a little Atlantic coast resort he knows well. Indeed, he used to live there before his wife disappeared at sea, never to be found again. As the ocean rejects a new corpse everyday, the mystery thickens and the list of potential suspects grows longer. This slows Molinat's progress as much as the cumbersome Leroyer, sent in to spy on him and hopefully impede his progress. The tension mounts and the ring involving the three young ladies in the grey mansion, the village idiot and the real estate agent starts spinning out of control.