The radiation from a fallen satellite might have caused the recently deceased to rise from the grave and seek the living to use as food. This is the situation that a group of people penned up in an old farmhouse must deal with.
During World War 2, a small plane off the south coast of America is low on fuel and blown off course by a storm. Guided by a faint radio signal, they crashland on an island. The passenger, his manservant and the pilot take refuge in a mansion owned by a doctor. The easily-spooked manservant soon becomes convinced the mansion is haunted by zombies and ghosts. Exploring, the 3 find a voodoo ritual in the cellar, where the doctor is trying to acquire war intelligence by transferring personalities into his zombies. But the interruption causes the zombies to turn on their creator.
By night they leave their graves, crawling, shambling, through empty streets, whimpering, pleading, begging for his blood!
Dr. Robert Morgan (Vincent Price) is the only survivor of a devastating world-wide plague due to a mysterious immunity he acquired to the bacterium while working in Central America years ago. He is all alone now...or so it seems. As night falls, plague victims begin to leave their graves, part of a hellish undead army that''s thirsting for blood...his!