Elsa and Laurent are very much in love and live with their teenage daughter Lucie in a small village in the Alpes-de-Haute-Provence. One morning, Elsa disappears whilst out jogging. As they begin to investigate, the police discover just how much she'd been hiding from her family.

Laurent realizes just how many grey areas there were in his wife's life. Who was the man she went to meet at the hotel? Who is the child whose photo she had always kept?

Laurent gives Elsa twenty-four hours to prove to him that she's innocent. Lucie becomes closer to her grandmother, but she also seems to be hiding things from her.

Cornered, Elsa and Laurent give themselves up. Questioned by Stéphanie, the best friend she hadn't seen for twenty years, Elsa adamantly having murdered anyone.

The investigation is drawing to a close, the murderer has confessed, but the police continue to have doubts. Laurent and Lucie try to get back to living a normal life again, but it's far from easy.