Tiny dead ghostlike Martian creatures are raining down on earth and cause chaos and destruction. Only scientist and "authority on the occult" Don Blant may help by contacting the ghost of his dead brother Allen. The latter tells him that the Martians shy away from human blood.
Bob and Jane are haunted by an old witch who was an ancestor of Jane's. Under the witch's bidding Jane turns into a were-cat and tries to kill her fiancé. But Bob gets help from a New Orleans "conjur woman".
Jim Thomas enters into a pact with a strange entity. Looking like a sack, the being offers Jim help in financial matters. In exchange the being can read Jim's thoughts. They start hassling over money and manners. Underestimating the thing's powers, Jim gets the short end of the stick.