Years after the appearence in the solar system of the immense, deserted spaceship named Rama by its discoverers, a second craft arrived, destined to become home for a group of human colonists. But now the colony has become a brutal dictatorship, terrorizing its own inhabitants.

Nicole Wakefield, condemned to death for treason, has escaped to the island of mysterious skyscrapers which the humans call New York. there she is reunited with her husband, but pursuit is not far behind and they are forced to flee to the subterranean corridors of New York inhabited by the menacing Octospiders.