Don Giorgio is a young, handsome priest and teacher in a convent. He has two girlfriends, Orchidea and Giulia. When he changes his mind and says he will go back to the Church, he is brutally killed. Not long after that, Giulia's throat is cut. Inspector Boito falls in love with Orchidea, who is also the main suspect, and gets ready to marry her. A curious boy named Ferruccio, who is locked up and given drugs, seems to be the key to solving the case. He saw one of the killings happen, but will anyone believe him?