Too many shape-shifting aliens and people, including those on his own side, are trying to capture him in order to use his star-traveling abilities for their own greedy ends. Bayard flees to Kaldar, a world devastated by atomic war and lousy with mutated rat-men and the Dark Brotherhood. At first, he’s just trying to stay alive. Then, he uncovers a mystery, one that, incredible as it seems, reaches all the way back to Earth. It could mean the alien enslavement of everyone, which means that Bayard is fighting for more than just his own survival. The Zero Stone is the third tale of a gung-ho Terran taking on the masters of an insidious and ancient alien conspiracy.