Scientist Arnold Kramer believes that rogue elements of the communist Chinese Army headed by fanatic General Chan Lu are using advanced burrowing machines in an effort to conquer the U.S. by placing atomic bombs under major cities.

In the opening, Las Vegas police are called for a report that Dr. Kramer is prone on a sidewalk telling people he hears movement underneath.

Shaw gets Kramer released and produces enough evidence to convince his superiors that the story is truel, and he is ordered to lead troops underground to defeat the red army and defuse the bombs.

[2] The Monthly Film Bulletin wrote: "Schoolboy comic-strip capers, involving subterranean constructions, hydroponic farms ("enforced growth under solaric light" the Chinese scientist explains), laser beams, nuclear bombs and sinister Oriental villains.

Nothing is quite so fanciful, though, as the finale, in which hero and heroine, with only ten minutes to run to safety after setting off an atom bomb, emerge in a volcano and stand looking at the glare of the nuclear explosion with not even a blink of their unshielded eyes.