Mankind has been all but wiped out by a Spanish Flu epidemic of 1918. To escape the disease, U.S. Navy officers took to their airships in search of isolated places to hide their families and make a new life. But now, three generations later, all of the Admirals must pay fealty to Sir Ironside, the man controlling the national helium reserve, paying him with plunder they've stolen from the savage tribes of survivors left on the ground. But when one of the marauding divers—Arthur, heir to his father's admiralty—gets stranded on the ground, he must learn how to deal with the savages and the slave girl who helps him escape from Malegant.