A cloaked figure slips into an exclusive psychiatric clinic and murders one of the female patients. Meanwhile, various sexuals liaisons are revealed. The mystery killer continues with his massacre: he beheads a nurse with a scythe, pushes a chauffeur into a spiked “Iron Maiden”,  strangles an older female patient, kills a nymphomaniac with an axe, and shoots a lesbian through the neck with a crossbow. Doctor Clay and the police set a trap for the killer using one of the attractive female patients as bait. However, they are not prepared for the onslaugth that follows…！