A thousand years in the future, society is run by computers, with not a gesture or activity unnoticed by their all-seeing detectors. Spacescrapers—three miles high, 1,000 stories, 1,000 people per floor—house 1,000,000 people. The divorce rate having climbed to 100 percent, the computers have made marriage almost illegal but adultery compulsory, with a resultant zero divorce rate.

In this setting, Bil and Alce meet, marry, and, their sense of history whetted by a few old books and photos, decide to rebel. They set out to find the central computer bank and pull the plug. Captured and imprisoned on a Floating Island (where the computers put criminals to get their just desserts), Bil and Alce escape. Their odyssey is gripping suspense and wonderful entertainment, with an ingenious depiction of man vs. machine.