Synopsis: From the first page of the Ballantine first edition: "Steve Ryeland knew that he was a criminal, who had failed the Plan of Man... but he could not remember his crime. Around his neck he wore an iron collar containing an explosive charge that would destroy him if he tried to escape; but what he had done that had put it there he could only remember in tantalizing fragments. And the Steve, still a prisoner, was given the world's most important job - to develop a "jetless drive", a new space propulsion system that would permit the forces of man to expand into the Reefs of Space, the half-mythical bodies that circled the solar system far beyond the orbit of Pluto. Ryeland had to succeed - or be relegated to the horrors of the living Body Bank."