Although mostly known for his bloody jungle-set cannibal films (Cannibal Ferox; Mangiati Vivi) and the splattery zombie-adventure Incubo sulla Citta Contaminata, Italian filmmaker Umberto Lenzi also made a number of interesting thrillers, including this engagingly incoherent giallo about an eyeball-stealing killer. The slayer's handiwork is first revealed when a female member of an American tour group is stabbed to death in Barcelona, and a teenager on an amusement park ride is murdered in a similar fashion the following day. Coincidentally (or perhaps not), a businessman named Mark Burton (John Richardson) finds out that his wife, Alma (Marta May), is in town, and remembers finding her unconscious once back in America with a human eyeball lying next to her. More murders follow, with a peasant girl, a lesbian named Lisa (Mirta Miller), and her lover (Ines Pellegrini) all attacked by the raincoat-clad killer. After yet another attack, Mark falls under suspicion, and must discover the killer's identity in order to clear his name. Bloodier than most of its contemporaries, the film presages the subgenre's spin into logic-free sensory assault with the following year's Dario Argento classic Profondo Rosso and features a star-studded cast including Martine Brochard, Jorge Rigaud, and Raf Baldassarre, as well as Argento regulars Tom Felleghy and Fulvio Mingozzi. Some video versions cut about four minutes of graphic violence.~ Robert Firsching, All Movie Guide