Season 4

The body of a young Romanian abandoned in the suburbs is found by Walter Battiston. The first suspect in the murder is an operator of the family home where the young man was a guest. Alessia Moretto zealously leads the investigation and, believing she has discovered the truth, she arrests an operator of the foster home.

Investigations into a road accident involving a mother and her child lead the police to investigate the Torrione area. Donna Rosalba, to avoid excessive police attention on the territory controlled by the crime family, turns over an alleged pirate to the investigators.

The lifeless body of a boy with a syringe still stuck in his arm leads the men of the S. Andrea police station to investigate an exclusive golf club where it seems that the boy had been involved in a clandestine relationship.

An inmate, Maria Coppola, seems to want to collaborate with the police who instruct her to find out if her cellmate, Teresa Pintauro, is actually responsible for a crime of which she accused herself, thus arousing more than one suspicion. In reality Coppola will demonstrate that he has completely different intentions.

A delegation of illegal parkers asks the policemen of the S. Andrea police station to be protected by the Pintauro clan which demands payment of the protection money from them. This is yet another sign of how Donna Rosalba's arrogance grows hand in hand with the power of the clan.

The investigations focus on a serial killer who chooses his victims among young disabled women: a blind young woman was killed and the social worker who assisted her was attacked. Suspicions focus on a convict who has already served a sentence for the rape and attempted murder of a disabled girl.

After a furious argument with Edoardo Valle, Luciano Russo disappears and his friend Genny is found dead. Some men of the police station believe that it was Luciano Russo who killed the boy, while others fear that he may have been the victim of an ambush planned by Donna Rosalba to avenge the death of her daughter Rita.

Deputy commissioner Cafasso's team manages to dismantle, after careful investigations, a highly organized gang of car thieves linked to the Neapolitan Camorra but with important ramifications abroad. The contribution of Commissioner Giorgio Pettenella, who has returned to service at the police station, is decisive.

A woman is killed and abandoned on the beach, the investigations focus on drug addicts with whom the woman had daily contact, working as a psychologist at the "Palomar" centre. The Police do not intend to leave out any investigative lead.

A well-known pop music singer found in possession of a dangerous synthetic drug agrees to collaborate with the police to arrest a drug dealer affiliated with the Pintauro gang. After the arrest of the father and the fugitive of the mother, the clan will be led by the young Pintauro, who has just returned from America.

Rosalba Pintauro and her son Tiziano seem to have disappeared without leaving any trace. An investigation that is particularly complex and delicate for the agents of the S. Andrea police station, also called to investigate the murder of a woman strangled in the bathroom of her home.

While investigating a robbery at a supermarket, the men of the police station come across a criminal game in which players-hunters chase a fleeing prey. It is feared that Alfio's father, suffering from Alzheimer's and missing for a few days, may be in the role of the prey.

The return of Sergio Amato accompanied by Stefano De Pretis is greeted with enthusiasm, while Pettenella listens attentively to some CDs that could hide the secrets of the Pintauro family. Alfio Donati is increasingly worried about his father's disappearance.

The discovery of a vast prostitution ring of girls from Eastern Europe suggests to Pettenella the idea that Silvia could work as an infiltrator together with Battiston, who will pretend to be a corrupt policeman. Meanwhile, a man is seriously injured by gunshots and, shortly after, the body of a second victim is discovered, killed by the same type of weapon.

The fight against trafficking in prostitutes is at a crucial, increasingly risky point: Silvia Esposito in the guise of Tiziana Blasi, the maitresse in contact with the prostitution ring, is "picked up" without warning by Carmine Torretta to accompany him to Ukraine to choose new girls to start off for exploitation.

Silvia's dangerous mission, infiltrated into a clan dedicated to the exploitation of prostitution, takes her to Ukraine. The already very difficult situation is further complicated when she is mistakenly arrested by the local police. Meanwhile, the elderly lady Adele is targeted by some roommates of her building.

Silvia's sacrifice to frame Carmine Torretta seems to have been in vain since the racketeer managed to escape. The inspector's frustration, transformed into anger, spills over on the woman from Torretta. For this reason, Silvia risks being excluded from the investigation.

The suicide of a wealthy lady, who had just undergone cosmetic surgery in a private clinic, offers Pietro Guerra the motivation to try to reconstruct the last days of the woman's life, also evaluating alternative hypotheses to suicide.

Luciano and Stefano investigate the murder of a barber in his shop. It will soon be discovered that the victim had made several enemies by carrying out a series of side activities such as multilevel selling and usury loans.

A bank manager's peaceful breakfast turns into a nightmare when three bandits break into his house, taking his wife and daughter hostage and forcing the man to go to the office with one of them to forcefully withdraw money.

A fire breaks out at a wine shop and the charred body of the manager is found in the rubble. The testimony of a passer-by leads the men of S. Andrea on the trail of a suspect. Claudia DiMaggio, who is under police protection, may be able to identify him, but she refuses to speak to Pietro Guerra.

The lifeless body of an antique dealer is found in an elegant apartment, all suggesting a robbery that ended in murder. Barbara saves two little boys from being attacked by a group of thugs but the two escape after stealing money from her purse.

Investigations into a dangerous arms dealer are proceeding slowly, a warehouse keeper seems to be the only link that could lead to incriminating those responsible. Following the latter's death, disguised as a suicide, the investigations go back to the high seas.

A psychotherapist is killed while talking on the phone with the deputy commissioner Cafasso who thus finds himself witnessing the crime from afar. Immediately the police direct their investigations on a psychopath, a patient of the study where the victim practiced her profession.

Claudia Di Maggio's betrayal threw Giorgio Pettenella into the deepest frustration. One thing is now clear: Claudia's collaboration with the police was determined by the desire to destroy the organization on someone's behalf.

The investigations of the S. Andrea police station are aimed at revealing the identity of the body of a man found in an escarpment, whose death dates back to about 15 years earlier. We follow the lead indicated by a woman who reveals to the investigators that 15 years earlier she was supposed to meet with her lover near the place where the body was found and that the man had never shown up for the appointment.