Mandrake and his team attempt to prevent "The Wasp" from stealing and using a new Radium invention.

Dr. John Meredith has been driven from civilization by the criminal activities of his twin brother Bradley Meredith. With his infant daughter, he settles in the African jungle, where his ability to cure the native ills has resulted in his virtual control of the Masamba tribes, who possess vast diamond mines coveted by a gang of crooks.

In the jungle near Angkor Wat in Cambodia, Mr. Moto poses as an ineffectual archaeologist and a venerable holy man with mystical powers to help foil two insurgencies against the government.

The entertainment duo Mitchell & Petrillo, en route to a USO show for troops in Guam, fall out of their plane and end up on the jungle island of Cola Cola, where the mad scientist Dr. Zabor is conducting evolutionary experiments.