On its mysterious voyage through interstellar space, a massive, alien starship carries its passengers to the end of a generations-long odyssey. For the great experiment conceived by the Ramans has failed. Rama III, with its carefully designed Earth habitat, as well as environments to house other intelligent species, has become a battleground. Instead of creating a utopia, the human contingent has brought forth a tyrant who seeks to conquer the other sectors of the vast Raman ark.