After months in a psychiatric institution, Chloe returns to find the criminal investigation division still in shock from Fred's death. She can't do field investigating, but Lamarck finds her a job in archives. Rocher, polite but distant, is in denial about his partner having set him up. Hyppolite, drowning his grief in bitterness, is persecuting all the new lieutenants appointed to replace Fred. In this tense atmosphere, Rocher witnesses the attempted kidnapping of a eighteen-year old girl. Detained and questioned, the perpetrator explains that he mistook the girl for his sister Coralie, who disappeared fifteen years ago when she was a little girl. Chloe is deeply moved by the story of this family who never got over the loss of little Coralie. Though forbidden to investigate, Chloe delves into the case. But in her efforts to help, she may reveal a truth even more appalling than the unresolved case of a missing child.