In this clever French thriller, Commissaire Wens follows a ruthless serial killer to an unexpected Parisian boarding house, where he must navigate a cast of quirky tenants and outwit a murderer who leaves calling cards at every turn. With the help of aspiring singer Mila Malou, Wens sets out to uncover the truth behind the murders, leading him to a surprising revelation that will test his wits and keep audiences guessing until the very end. As the body count rises, Wens finds himself in a desperate game of cat and mouse with the killer, who seems always one step ahead. Will he be able to solve the case before it's too late?