Sergey Ratny is an engineer-reenactor from the 25th century Earth. As a result of a shipwreck, he ends up on a planet where the level of technology does not exceed what it was on his home planet at the beginning of the 20th century—though technological development has taken a slightly different direction… The locals preferred steam to internal combustion engines. Here enormous steamships ply the sea, on land steam vehicles run, steam tractors work in the fields, and in the sky giant airships rule. However, as once on his home planet, a bloody war is raging here, and Sergey is unwillingly forced to become a participant in it. He begins building the first heavier-than-air machines in this planet’s history—because only airplanes can withstand the crushing power of the enemy airships. The battle for dominance in the air begins…