Johnson hires nurse Nadine (Beverly Garland) to look after him in his house. Her boss, town physician Dr. Rochelle (William Roerick), is under Johnson's hypnotic control after finding out about his patient's peculiar blood cell structure. With a limit on the number of transfusions he can be given, Johnson takes to murdering locals and draining their blood. Adding to his victims are a strolling Chinese-American man, a sleazy door-to-door vacuum cleaner salesman, and a trio of homeless male drunkards. The police are mystified by these "vampire killings".