A diving instructor has been found dead on a beach in Toulon. Tom becomes involved in Lola's investigation as the prime suspect is one of his informants.
Michaël, a young apprentice in a traditional soap factory, is found dead, lying in a pool of soap. While everything seems to point to his having been murdered, the mystery remains: his body was discovered in an airtight vat room.
Tom and Lola investigate the murder of a man found stabbed to death in the basket of a hot-air balloon. The second passenger is nowhere to be found and the victim's wife seems to be hiding something. At the same time, each of the two flatmates has signed the other up for a job interview at the financial brigade, in the hope of keeping his job with the criminal investigation department. During yet another argument on the subject, Lola confesses that she saw Cynthia with another man the day before.
