S4·E13 Under Blackmail / The Last Challenge

Roberto discovers that Francesca and Mauretta have been kidnapped, after which a phone call to his cell phone orders him not to ask anyone for help. Roberto soon discovers that there are clear and dangerous connections between the kidnapping and Paolo's murder, reaching the conclusion that the X° Tuscolano is being monitored through spy microphones. Meanwhile, Luca and Corrado deal with the case of a woman who disappeared after a car accident.

Giulia and Mauro call the forensic team to remove the microphones hidden inside the police station. Someone who has free access to the rooms of the X° Tuscolano has managed to place them undisturbed, perhaps one of the most unsuspected people. The solution to all the mysteries is about to be revealed once and for all.