Parisian Vautier mobilizes Matthieu Pérac’s team to look for his teenage daughter Laura, which he reported missing months ago. When interviewed the right way, sole school friend Amandine Verganti reveals how class bitches cruelly set shy Laura up with a fictitious date. After the trails from there to an ex-con pedophile and mythomaniac music teacher as well as art teacher Catherine Delage run dead, the father admits having faked an anonymous letter. The team reevaluates a suspect and comes up with another theory, based on a twist after a much earlier, never solved …