The body of a teenager is found in the rubble of a building. Warned by Herville, Laure is convinced that there is a link with the investigation into the murder of Mercier and is trying to recover this case. In parallel, she continues her investigations to shed light on the rape of Josephine. Furthermore, the ex-wife of Fromentin is worried because she is unable to reach their son. The panic spreads to the policeman because Ruben does not answer his multiple calls either.

The fiasco of the search of the Roma camp leads the police to resume the investigation of the Bac. Arnaud Beckriche asks Laure and his colleagues to focus their efforts on Jolers and Calvi to establish the extent of corruption. Herville has confirmation that one of his men has warned the mayor of the operation to make it fail. To appease her revenge, Josephine takes action. In addition, Romy's health is improving.