Aline lost her 17-year-old son in a brawl at the bottom of a tower. Justice sentenced his murderer, Maxime, to nine years in prison. Five years later, she meets him at the bend of a supermarket aisle, fresh out of prison working as an apprentice plumber. He doesn't recognize her. So Aline comes up with this crazy plan to bring Maxime to Les Adrets with the pretext of redoing the plumbing in her childhood home. His idea: poison him with rat poison.