Christian is trying his best to adapt to university life, Martin needs to learn to manage his break-up, Étienne and Simon continue the arduous task of taking their lives in hand... For the four friends, being in their fifties is definitely no walk in the park.

Isaac Lowe, famous business lawyer, is about to hand control to his daughter Mélissa. But as she prepares to conduct a merciless war against even the most untouchable criminals, little does she realise that her own father is also involved in some very murky affairs...

Marianne Vauban, an examining magistrate who favours unorthodox methods. Accompanied by her two assistants, she investigates cases as complex as they are varied. In parallel, she continues her quest to discover the murderer of Zacharie's mother, the young and gifted teenager whom she'd taken under her wing and her roof.