In Naples at the end of the 19th century, Nicola Bellizzi dreams of becoming a lawyer. However, when he seeks the reason that people are reluctant to help him in his goals, he discovers that some of his blood relations are high-ranking members of the Mafia. He tries to break away from his family obligations, but falls into a life of crime and violence.

In Naples, gangsters have seized the American ambassador. The authorities respond by assembling a special squad; to command it is Borri, a former commissioner who has a personal vendetta against the racket.

Southern Italian workers relocate to Milan and adjust to life in the city, where they reside in a house together. Among the group are country boys Gigi and Carletto, who are overwhelmed by urban living. While some find work at a hectic restaurant, others are employed at a grim slaughterhouse. However, when some of the migrant workers are unable to make ends meet, they resort to theft, worsening their situations.