In the early 22nd century, with the world suffering from a continuing ice age, food production in the United States is controlled by the Bureau of Sustenance. Private property has ceased to exist, and all citizens are forced to live in huge towers. However, a small group of people have managed to remain outside. Unfortunately, wisps of smoke from the group's uncontrolled fire have been seen from a Bureau helicopter and reported. Sustainers Amos Benton and Jake Martinez soon are sent from Tower Seven to search for the "outsiders."