Of the hundreds of giallo thrillers produced in Italy since La Ragazza che Sapeva Troppo initiated the form in 1963, this dreadful effort from writer/director Giovanna Lenzi may be considered the genre's absolute nadir. Police discover two dead bodies with their heads turned inside out (quite unconvincingly, it should be noted), and a black-gloved killer spikes a witness' coffee with poisoned sugar at a tacky disco. As the killings continue, it becomes obvious that there is more than one mysterious assassin causing female victims' faces to implode by poisoning them with snake venom. Almost invariably, their death throes lead their breasts to become exposed, giving some insight into the lack of respect with which Lenzi treats her audience. This is a tasteless, vulgar exercise loaded with dreadful special effects by Aldo Ciorsa and Sergio Basile, music stolen from La Casa con la Scala nel Buio, copious nudity from performers best covered in clothing from head to toe, and a production design that is so unattractive as to verge on the criminal. The level of gall shown in this tawdry film, supposedly based on the Henri Becque play La Parisienne, can best be illustrated by a scene in which a terrified witness is menaced at a phone booth by a figure in a dark coat, only to see the man doff his coat and begin break-dancing. Stupefyingly awful in almost every respect, the film is particularly saddening due to the fact that Lenzi's direction was supposedly "supervised" by her husband, Sergio Pastore, a man who had been responsible for one of the genre's most audaciously entertaining films (Sette Scialli di Seta Gialla). Saverio Vallone stars with Michela Miti, Giorgio Ardisson, and Gianni Dei, while Lenzi makes an appearance under the pseudonym Jeanette Len.