A quiet Sunday in Rome... for the police officers of the Mobile Squad, however, Sundays, like the rest of the days, are never quiet. This Sunday in particular, everything happens. It would be Ardenzi's birthday but between stalking, drug trafficking and women who want to throw themselves into the Tiber, the day seems to never end.

The Mobile Squad is dealing with a typical day at work in the Capital. An old friend of Ardenzi, a well-known restaurateur in the historic center, turns to the commissioner to solve a problem with his son. Meanwhile, a young girl who is not yet of age is taken to the police station together with the man who lured her.

Zaccardo, head of the Section, informs Ardenzi and Sabatini of an upcoming very important operation to capture a fugitive in a Roma camp in the Capital. They must prepare and carry it out as best they can. This obviously while emergencies arrive at the Police Headquarters.

Today is the day of the blitz. The team is finalizing the final preparations but the police headquarters receives a report of a woman run over on Lungo Tevere, and moreover the daughter of a repentant.

While at the police station Claudio Sabatini is looking for a way to free Bradic, who is being held awaiting questioning, without arousing the suspicions of his colleagues, Ardenzi and Sandro are dealing with the case of a Pakistani girl stoned to death in the street and Isabella is dealing with her first serious friction with her boyfriend Giulio who ends up slapping her with serious consequences.

Bradic's death at the police station and at the hands of Marcello, forces the commissioner to put the young policeman under investigation and for this reason Oliviero, feeling misunderstood and unjustly accused, runs away and disappears. Ardenzi is worried about the boy, he wants to find him and it is his job to clarify the dynamics of the facts; Claudio Sabatini also needs to find Marcello.

The death of Marcello has shocked the entire team but the worst blow was suffered by Roberto who feels responsible for the boy's disappearance and is now determined to understand what happened. In the meantime, Sandro and Giacomo discover a prostitution ring run by chinese where underage girls are enslaved; while Isabella and Valeria manage to save Giulia, a woman mistreated by her husband, who for the love of her daughter finds the courage to report him... but for Isa, a champion of mistreated women, the real troubles begin now: on her PC, in fact, an order to stop from an anonymous but very threatening sender arrives.

Ardenzi, following the notice of investigation, appears before the judge with his lawyer and discovers that he is being investigated for incitement to suicide.