Five years before, the American supercomputer Colossus and the Soviet supercomputer Guardian were united—combining their data, their analytic powers, their learning & growth capacity. In the few seconds of that process, they became one Colossus—master of humankind. Programmed to solve humanity's problems, Colossus solved forestalled nuclear holocaust, eradicated poverty and the frustration and violence it breeds. Soon there was nothing for people to do—but obey. Some made Colossus their God, & Charles Forbin was their Pope. Others wanted to be free of Colossus—for Colossus was also ruthless beyond any human tyrant ever—& they wanted Forbin as their deliverer. Either of these movements might get Forbin killed. He is appalled & disgusted by the religious cult, terrified by the rebels—who haven't a chance, as he knows better than anyone on earth. Then Forbin is handed the key to the overthrow of Colossus—or is it? He must commit his life to the chance that it is, just to begin with. Then he must commit the earth to the shadowy motives of the mysterious source of this new power.