In the twenty-sixth century Earth is a war-ravaged backwater. Mars and Venus are terraformed worlds recovering from a dark age and ruled by autocrats. The Asteroid Belt is the industrial hub of the Solar System. Subcommander Walker Tsume left Earth twenty years before. He joined the Martian Space Navy to find a new home. Walker is a brilliant tactician and pilot, but as an immigrant and outspoken maverick, his career stalled, leaving him at a desk deep in the bowels of Phobos. When the Martian Empire and the Asteroid Belt Confederation go to war, Walker receives command of the corvette Odin and a barely qualified crew. Walker modifies his ship's systems in defiance of orders and leads Odin and his crew on a perilous mission to Jupiter's moons. But not everything is exactly as it seems...