When teenager Lea Morel does not return home from a music festival, her desperate parents contact the police. Lieutenant Molina, freshly transferred from Paris, uncovers areas of Lea's life that her family knows nothing about.

Lea's father Julien is in police custody for lying about his alibi and refusing to give his actual whereabouts on the night of his daughter's disappearance. Molina and Camille discover that Lea has beenintroduced to single-seater racing, but wonder how she managed to pay for lessons.

Julien is woken by a frantic message on his mobile phone from Lea asking him to call her. Molina and his team trace the call to the train station. Nicolas, a waiter at Morel and Sons restaurant, shows Julienthe illegal police radio interceptor he has in his car, and as Julien listens to the communications, he begins to shadow their investigations.