In the domed city of Atlanta, after the breakup of the United States, a young writer named Julian Cawthorn is in trouble. Because he insulted the daughter of a public official, Cawthorn is out of work, and virtually unemployable. He begs a temporary job on the city newspaper and finds himself assigned to cover the first public appearance of the aliens Cygnusians, travelers from outer space who have been living in seclusion in Atlanta while visiting Earth.
A Christian revivalist dictatorship rules Atlanta; church services are as much social as they are religious events. When one of the aliens chooses to appear at a church service, Julian watches as the first alien from space stands up and is "saved". The alien's voluntary salvation is taken as a sign that the state religion is indeed the one true religion, and minority groups, previously tolerated, are attacked by gangs, leaving Atlanta in turmoil.
The service is a turning point in Julian's life. He is hired by Fiona Bitler, hostess to and protector of the aliens; at her invitation he goes to work in the secret alien enclave. In this environment Julian comes to know the fascinating aliens. He is mystified by the aliens' interest in his personal life and cannot understand how they have acquired so many oddly human characteristics in their brief period on Earth.
