The bartender Giuseppe Alfò threatens to commit suicide and Marshal Rocca, who has come, seems to be able to make him give up his intention. The same evening, Alfò is found suffocated in his car: the most accredited hypothesis, that of suicide, does not convince the Marshal, who during the investigation knows not only Alfò's wife, but also Margherita, his new flame .

Marshal Rocca finds Serafino, a penniless old man who has received an eviction order, a place in the Villa Rosa rest home, in order to prevent his home from burning down as he threatened to do. The first night the old man is hosted in the structure, it catches fire. Serafino is the main suspect, but the marshal is convinced that the track is another.

The son of marshal Rocca, Giacomo, met a girl in a disco, accompanied by a friend who wore flashy clothes and a showy pair of boots. The same girl is then thrown out of a moving car, after being beaten up, without documents with her. The marshal will first have to dispel the doubt that his son is involved in the affair, and then investigate the clandestine prostitution ring.

Marshal Rocca's police station is shaken by the events of Antonio Fait, one of the best men, involved by his drug addict girlfriend in a shady tour. The marshal comes to find out and, together with his group, carries out a blitz in an abandoned paper mill to catch the drug traffickers red-handed, without however finding any evidence. Claudia, Antonio's girlfriend, is accused of having tipped off the carabinieri and beaten by pushers, so much so that she lost the baby she was carrying. Antonio, who returns to the paper mill to take his revenge, is killed there: Marshal Rocca will not rest until he manages to capture the whole clan.

Carabiniere Michele Falcetti arrives in Viterbo to replace Antonio Fait, killed a month earlier. A new case prevents Marshal Rocca from taking the exam for the passage of grade: Roberto, his youngest son, is taken hostage during a robbery in a supermarket and his colleague Banti is wounded in the shooting against the robbers. The marshal manages to find his son and have all the robbers arrested, but he has to give up the precious collaboration of brigadier Cacciapuoti: the latter, caught by a heart attack during the investigation, goes on leave for health reasons.

A friend of Daniela's, Sandra Varano, mysteriously disappears: Daniela had seen her arguing with Giorgio Massenzi, her boyfriend, who is immediately questioned by Marshal Rocca. Even Daniela, however, seems to be hiding something. It then turns out that the girl had turned to a nurse for an illegal abortion and had run away from home to escape her father and the father of the child. Brigadier Cacciapuoti, despite being on leave, can't help but help his marshal.

Domenico Scala, a violent and dangerous criminal, has escaped from prison: Marshal Rocca is in danger because the offender holds him responsible for his brother's suicide and is determined to take revenge.