The City of Gold and Lead — John Christopher

Will, Beanpole, and Henry have managed to es cape the Tripods. But instead of living in safety, in the small Swiss community of free people, they have chosen to embark upon a mission that may yet again cost them their lives.

Each year, a series of Games is held in Germany. Those who win the competitions win the honor to serve the Tripods. Those who are Capped consider this the highest honor. And those who are free know that it is an ideal opportunity to infiltrate the City -- and, perhaps, free the world.