The nightmare ""City"" of the future, hints Hoover broadly, is already here. Her City, much like ours, is congested, dirty, infested with rats and ""crazies."" And what's so futuristic about teaching machines, micro-cookers, food-prep-labs, ID cards and ""life files"" on everybody? Her small elite lives graciously on the 80th dome-enclosed level and can see daylight. On the lower levels, underground, subsist the servant classes in benightedness. The system keeps them ignorant, so they won't rebel. No one reads, except 11-year-old ""too bright"" Amy, and reading, it turns out, is the key that sets her free. She and ""psychotic"" Axel, who actually came in from Outside via a hard-to-grasp accident, make their way, not altogether believably, past ubiquitous ""watchers,"" locked gates and mechanized turnstiles, up to the 80th level. There they are judged risks to the system and put Outside, where all is barrenness, post-unspecified-cataclysm pollution, unimaginably vicious monsters, and roaming rejects from the City. Hordes of these attack the children; but Axel's people, real human beings, come to the rescue in the nick of time. Yes, but how had they survived and managed to save, or reclaim, their land? That these questions aren't answered weakens the hope at the end, and the familiarity of the grim landscape lessens their urgency.