Millennia from now earth is ash and cold silence. Four different worlds have evolved from the ancients. Great City, the only structure on the surface, contains thousands of citizen-units who function without question because there are no more questions. The Space States are a post-capitalist federation of four enormous mother ships far flung through the universe seeking a replacement for earth and not finding one. Beneath the surface SubTurra is a massive corporate power ruled by one man with no restraints. Last, stone-people are hidden and silent, traveling the underground wilderness in small bands and leaving no footprint. These four worlds are put on collision course when an invaluable Prime Researcher begins to dream then escapes from Great City determined to be free.