A young couple journeys to Mystery Island to rescue the girl's father, who is being held prisoner by the evil Captain Mephisto, a pirate from 200 years ago who uses his Transformation Machine to travel forward in time and disguise himself as one of the four owners of Mystery Island.

Produced at the same time as the more well-known The Twilight Zone (1959), this series was an extension of the tradition of radio horror and supernatural dramas such as Light's Out, The Mysterious Traveler and The Witches Tale. As with the Twilight Zone and the radio programs each tale was book-ended by an introduction and conclusion by a host. However, rather than creating fictional stories with supernatural twists and turns, this program sought out "real" stories of the supernatural, including ghosts, disappearances, monsters and the like, re-creating them for each episode. No solutions to these mysteries were ever found, and viewers could only scratch their heads and wonder, "what if it's real?"

A master criminal called The Spider puts the famous detective's brother under a hypnotic spell and turns him against Dick.

A gang of street kids work with the FBI in their attempt to find and rescue their leader's father, a scientist who has been kidnapped by a terrorist group.

Flash Gordon, Dale Arden and Dr. Zarkov return to the planet Mongo for an antidote to the Purple Death, which wreaking destruction on Earth. However, Ming the Merciless has other plans for them.

A group of street kids battle a terrorist gang led by a Japanese spy.

Buck Sherman and Jake Jackson, a couple of evil carpetbaggers, illegally enter a Navajo reservation to prospect for gold and end up killing Aranho, the Navajos chief. Black Arrow, presumed Aranho's son, refuses to kill the Indian agent, Tom Whitney, in revenge, as demanded by Navajo law. Then, he is driven off the reservation for his reluctance to kill Whitney and decides to join forces with Pancho, Mary Brent and the agent to go in search of the men who killed the chief.