The Mystery of the Trail of Terror (The Three Investigators, #39)

The Mystery of the Wandering Caveman (The Three Investigators, #34)

Three young sleuths investigate the disappearance of a caveman's bones from a museum and uncover skulduggery at a science foundation.

The Mystery of Death Trap Mine (Alfred Hitchcock and The Three Investigators, #24)

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

The Secret of the Haunted Mirror (Alfred Hitchcock and The Three Investigators, #21)

The Mystery of the Scar-Faced Beggar (The Three Investigators, #31)

A wallet dropped by a scar-faced beggar sets the Three Investigators on the trail of bank robbers.

The Mystery of the Creep-Show Crooks (The Three Investigators, #41)

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

The Mystery of the Blazing Cliffs (The Three Investigators, #32)

Wealthy eccentric Charles Barron is convinced that aliens are planning to fly to earth and take him away. The detective trio resolves to prove that Barron is being taken for a ride--but not by hostile aliens.

The Mystery of the Flaming Footprints (Alfred Hitchcock and The Three Investigators, #15)

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

The Mystery of the Missing Mermaid (The Three Investigators, #36)

Something is fishy in Mermaid Court!First a little boy mysteriously vanishes, then a treasured statue of a mermaid disappears. An actor tells outrageous lies...a dog lover gets an unexplained bite...and lights flicker in the windows of the haunted Mermaid

The Mystery of the Cranky Collector (The Three Investigators, #43)

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.