In this classic 1957 science fiction horror film, an extraterrestrial humanoid named Mr. Johnson arrives on Earth, disguising himself as a human to acquire fresh blood for his dying planet's inhabitants. Johnson's mission becomes entangled with a teenage girl, a nurse, and a police officer as he surreptitiously secures the blood of humans to test it as a treatment for his own fatal disease. As Johnson's sinister plans unfold, the lines between good and evil are blurred in this eerie tale of mind control, teleportation, and murder.