The story begins with Buck Rogers (Buster Crabbe) and Buddy Wade (Jackie Moran) in the midst of a dirigible flight over the North Pole. They are caught in a savage storm and crash - but not before they release an experimental substance called Nirvano Gas that they hope will preserve them until rescue can arrive. The Nirvano Gas works, but the dirigible is buried in an avalanche and is not found until 500 years have passed. When Buck and Buddy are found, they awaken to a world ruled by the ruthless dictator Killer Kane (Anthony Warde) and his army of "super-racketeer". Only those who live in the "Hidden City", run by the benevolent scientist Dr. Huer (C. Montague Shaw) and his military counterpart, Air Marshal Kragg (William Gould), resist the criminal rulers of Earth.
Buck and Buddy join the resistance, and they set out for Saturn, where they hope that they can find help in their fight against Kane. Saturn is run by Aldar (Guy Usher) and the not-so-aptly-named Council of the Wise and Prince Tallen. To the dismay of Buck and Buddy, they also discover that Kane has dispatched ambassadors of his own, headed by his loyal henchman, Captain Laska (Henry Brandon). The serial then becomes a back-and-forth struggle between Buck and Kane to secure the military support of Saturn for the struggles on Earth.
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