18 year-old Laëtitia has gone missing, her scooter found early in the morning. The police rapidly manage to piece together her final hours and arrest a suspect

Despite an arrest being made, no-one knows exactly what has happened to Laëtitia.

New statements from witnesses enable the case to advance and the area being searched is widened. At the same time, the teenager's family is received by the French president.

The pathologist reveals that Laëtitia had been strangled, the information is made public; the relationship with the judges has become very tense; Laëtitia's body has still not been found.

Jessica remembers that Laëtitia, shortly before her disappearance, had wanted to speak to Christelle, one of Gilles' daughters.

Social worker Béatrice Prieur agrees to meet and discuss the victim's personality and their evolution over the past few years.