PolicecommissionerHervilleisfounddeadinaChineserestaurantinthe13tharrondissementofParis.GiloumustbreakthenewstoLaure,whoisbeingtreatedinaPolicerehabilitationcenter.Nowinchargeoftheunit,GiloubeginsinvestigatingwithAli,ayoungcop,freshoutoftraining.Theyquicklyfindthemselvesonthecaseofabreak-ingonewrongandthetrailof15-year-oldRyan,ajuveniledelinquent.RobanlearnshemustsoonretirebutstillmanagestooverseetheHervillecase.Awaitingtrail,Joséphinestruggleswithlifeinprison