At the Pentagon, Navy officers and scientists are stumped. Two scientists mysteriously disappeared in Antarctica. They call in "men capable of handling the unknown." Ace, Rocky, and Red fly off, picking up Prof along the way. Off New Guinea, Prof is astounded to find a volcano rising from the sea bed. In the Antarctic, the Challengers snow-tractor toward the mystery spot. The tractor bogs in a snowstorm and needs repairs. Ace and Rocky explore and fall through thin ice! They land on a futuristic bridge. Above, Prof and Red are captured by skinny orange aliens in bubble-suits.