Alexander Armitage is back in the thrilling conclusion to The Iron Chronicles. Refusing to return to Eton College, Alexander joins the Sky Raiders as a crewman on the aero-dirigible, Sparrowhawk. With Genevieve, the barons daughter, captured by the vile Colonel Hendrix, Alexander races to the top of the world, and discovers the terrifying machines created by the Knights of the Golden Circle to enslave the world. Betrayed by his allies, and aided by a mysterious woman and her clockwork owl, the race is on from the snow-covered peaks of the Himalayas, to the shining capital of the New World. In a steam-powered Victorian world where pirates prowl the sky and secret societies determine the future like a game of chess, Alexander learns that it is not gender, race, or age that determines a warriors worth as he is forced to choose between becoming a knight, or one of the Four Iron Horsemen.