Planet Urth: The Underground City (Book 3)
by Jennifer and Christopher Martucci
Avery, June and their friends are being hunted. They need to find fuel so that they can travel across the country to the underground city, to a place where humans live safely, free from the terrors above ground. But once they make it there, will it be the idyllic paradise they imagine it to be or will it be worse than the current nightmare in which they live?