The new captain of the Carabinieri, Fabio Leopardi, arrives in a quiet provincial town, called to investigate the possible existence of a satanic sect which has led to the death of three people the parish priest of the town, who died in an alleged accident, the captain of the carabinieri, apparently dead by suicide, who was investigating the death of the priest, and a young student, found dead in a ditch, who behind her good girl appearance hid the use of narcotic substances and the practice of rituals satanic. Despite a series of misdirections, Leopardi will be able to shed light on the case.