Enraged jaguars, violent winds of hurricane force, and a mysterious cave-man who roams the jungle around the Mayan village in Yacatan are only a few of the perils the young inventor encounters during his thrilling new expedition. But even more feared by Tom and his friends is a band of phantom bandits intent on using deadly means to force them to abandon their project as Tom tests his latest inventions: his "parachute" plane and his electronic retroscope...