Objective, unbiased and hyper-rational, the Vulcan 3 should have been the perfect ruler. The omnipotent computer dictates policy that is in the best interests of all citizens—or at least, that is the idea. But when the machine, whose rule evolved out of chaos and war, begins to lose control of the "Healer" movement of religious fanatics and the mysterious force behind their rebellion, all hell breaks loose.

Written in 1960, Philip K. Dick's paranoid novel imagines a totalitarian state in which hammer-headed robots terrorize citizens and freedom is an absurd joke. William Barrios, the morally conflicted hero, may be the only person who can prevent the battle for control from destroying the world — if, that is, he can decide which side he's on.