Shot accidentally into space while experimenting with the radio transmission of matter, Myles Cabot had landed on Venus, and in two short years he had changed the entire course of civilization on that planet. He led the human race of Cupians to victory over the huge ant men, married the lovely Cupian princess Lilla, and proceeded to make scientific discoveries in peace.
Then, in one sweeping blow, the ant men made a comeback and Cabot found himself alone in an alien land, his King murdered, his wife unprotected in a castle far to the north, his people vanquished. Northward he marched, a million obstacles in his way, with only his desire to help his adopted people and his loved ones to keep him going.