On Christmas Eve, Léa and Juliette, a couple, want to rob a supermarket that Juliette knows is empty of surveillance on this festive evening. But, as much for each of them as for Eric, the vigil who is there after all, nothing will happen as planned. Besides, shortly before leaving him alone, the store manager gave Eric a gun, just in case.

Except for Amine and Kimmy, the young couple of neighbors she meets regularly, visitors are rare in Constance Brunel's antique store. Loneliness is also her life. One night, Amine, in a panic, seeks help at her house: Kimmy has fallen badly when she slipped and she has killed herself. Thinking that the police will not believe this version because of his judicial past, Amine borrows Constance's car to take the corpse and make it disappear. In the days that follow, this shared secret brings Constance and Amine closer. But one morning, an anonymous letter accompanied by photos demands a ransom: someone in the building has seen everything, the blackmail begins.