Here is an adventure story complete with such traditional ingredients as a lost tribe, sinister traces of a mighty former civilisation, and a hero, Roy Complain, who, purged by peril, comes eventually to find himself. But these classic ingredients have undergone a romantic metamorphosis: no tribe has ever been more thoroughly lost than the Greene tribe, and when Roy Complain and Priest Marapper set our for the fabled region called Forwards, they are heading for a series of shocks which will surprise the most hardened reader. For this is science fiction at its best, a realm where the logical happening is the unexpected one.