In blizzard-wracked Florida, Nelson contacts a meteorologist who may be able to help explain the strange weather conditions. That night, however, the scientist is abducted, and "programmed" to kill Nelson. When his first attempt fails, he comes aboard Seaview when she sails to investigate the source of the problem, and continues his efforts.

When the King of a small but friendly nation is assassinated, Seaview is assigned to take the young Crown Prince back home to assume his throne. Neither Nelson (who gets turned out of his own cabin) nor Crane are used to handling children. Help arrives in the form of a mysterious flute-playing old man who befriends the boy after he is picked up at sea.