The film is the result of a planned trilogy about the kidnapping and murder of Aldo Moro by the Red Brigades first announced by director Grimaldi in 2003: shot in the UK on a low budget, the project was never completed because of lack of funding and other issues, and the existing footage from the first two planned installments was condensed into a single movie and released on DVD in 2009.

Luciano Persichetti is hypersensitive and convinced that he has paranormal powers. Susanna, a parapsychology student with whom he is in love, tries to help him interpret the paranormal warning messages he is receiving. When Luciano turns out to be haunted by a mysterious killer who calls himself "The Guardian Angel", Susanna discovers that Luciano's paranormal powers are not real at all.

The film is set in the period of fascism and is represented through the story of the general inspector Vincenzo Trani.

After graduating in correspondence detective, Riccardo Finzi arrives in Milan. The first case he deals with is the death of a young maid. Cockpit in a surreal yellow from a novel by Luciano Secchi.

A black-out occurs during the meeting of a gang of criminals. When the light is back one of them is found killed with a stab on his back and all the clues point to a penniless man who had an argument with the victim a short time before the murder.

In Rome, a vagrant finds the body of a teen girl, her throat professional slashed. Police inspector Olmi uses his brutal and violent methods to follow a trail that leads him toward high government officials. When his methods leave an innocent bystander dead, the corrupt officials have an excuse to get Olmi transferred to a coastal town where the pace is slow and he has time for a romantic dalliance. Soon, Olmi discovers that fishing isn't the only local occupation, and out comes his gun and his ruthless tactics of investigation.

When a crime boss sends out his thugs to terrorize an entire city, they do whatever they want, which includes anything from petty theft to robbing the police station in broad daylight. Napoli spara! (internationally released as Weapons of Death and Naples shoots) is a "poliziottesco" film directed by Mario Caiano in 1977. It is an unofficial sequel of Napoli violenta, of which reprises the character of Gennarino (still played by Massimo Deda).