The Three investigators mystery series ;

The three investigators, aided by their friend Allie, try to untangle the unusual circumstances surrounding an abandoned silver mine.

The sighting of a UFO leads the Three Investigators to uncover a bizarre confidence game.

A statue of a mermaid proves to be a vital clue when the three investigators set out to trace a missing child.

While accompanying Pete's inventor grandfather to New York where the old man plans to sell his new invention, the Three Investigators find themselves in the middle of a dangerous spy case.

Three young detectives try to solve a mystery involving a gold Indian amulet and a laughing shadow that appears to them in the night.

The Three Investigators foil a plot to kidnap the son of a political leader in an African colony.

Three junior detectives investigate a mystery involving an Oriental chest, a sunken ship, and a baffling dual identity.

When an ornery book collector disappears, the Three Investigators break into his secret computer files in search of clues and gradually uncover his mysterious past.

When three junior detectives search for a valuable old Spanish sword lost since the Mexican War, the headless statue of a horse yields a clue.

An old trunk involves the three investigators with dangerous criminals seeking a cache of stolen money.

The Three Investigators set out to find Mr. Allen's Irish setter, one of six dogs missing from the neighborhood of Seaside, but he insists there is a dragon living in the cave in the cliff under his house. More interested in the dragon than the missing canines, Jupiter, Pete, and Bob explore the cave—and come face-to-face with the terrifying dragon! Chased by menacing scuba divers on the beach and by an eccentric neighbor on the cliff, The Three Investigators plunge into a case where danger lurks at every turn. The Three Investigators must decide, are they willing to risk their lives and return to the cave to for the clues they need to solve The Mystery of the Coughing Dragon?

Three young detectives try to trap an invisible vandal who has been breaking car windows all over town.

While attending a week-long family reunion on a California island, the Three Investigators find their photographs of the event hold an inordinate interest for someone else, and receive clues to that unknown identity from both an ancient and a modern boating accident.

Searching for a legendary pirate treasure, the three investigators find a band of modern day pirates.

Three young sleuths uncover a coven of witches when they search for the missing memoirs of a movie star.

Three young detectives search for a stolen statue only to find that it has mysteriously come to life.

The three investigators become involved in witchcraft when they try to rescue a woman from the influence of snake worshippers.

Summary:When an eccentric local artist disappears suddenly, the three investigators look into the matter

Three young sleuths uncover a mystery buried since World War II when they come to the aid of a trouble-plagued environmentalist who is protesting the drilling of off-shore oil wells.

The Three Investigators solve a case involving an international gang of art forgers.

The Three Investigators tangle with a couple of shady producers of horror films when they try to track down a runaway teenager.