At a top-secret government base near the small town of Two Rivers, Michigan, scientists are investigating a mysterious object discovered several years ago. One late evening, local residents notice strange lights coming from the laboratory. Waking up the next morning, they discover that their city has been literally cut off from the rest of the world and... placed in a new one!

Soon the city is found by the confused leaders of the new world and at that moment the inhabitants of Two Rivers realize that they have found themselves in a society of a rigid theocracy. Authorities known as the Bureau of Religious Decency have ordered Linnet Stone, a young ethnologist, to study the new arrivals and report her findings to the lieutenant in charge. What Linnet discovers will shake the philosophical foundation of her society and inevitably lead to a power struggle centered on a mysterious object that government scientists investigated Two Rivers when the city crossed between worlds.