When a pair of detectives starts investigating a mysterious death that took place in a haunted house, they begin to encounter strange occurrences.

A misunderstood teen fights to save his town from a gelatinous monster from outer space.

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From his observatory, Scottish professor Elliot (Raymond Bond) keeps close watch on Planet X, whose orbit is coming close to Earth. During the planet's approach, an alien ambassador appears but falls prey to maniacal scientist Dr. Mears (William Schallert). Returning the distinct lack of hospitality, the extraterrestrial uses his otherworldly powers to turn those he encounters into mindless drones. Elliot tries to stop the creature before everyone is turned into a zombie.

A rescue team is sent to Mars to bring back an astronaut who claims that a Martian monster killed his team. As they return to Earth, they sense the presence of the creature in the spaceship.

A man (Lionel Atwill) uses mind over matter to replace his legs, then hunts the doctors who took them.