The story is set on a planet called Klydor in the distant future. Earth is ruled by a ruthless buracracy known as the Organization. One arm of the Organization, Colonization Section, or ColSec, establishes colonies on other planets for the wealth and benefit of the Organization. Because colonizing wild planets is a dangerous task, ColSec frequently sends unwanted, "expendable" juvenile delinquents on their colonizing missions. If they perish, the Organization can always find more "discards" to send on these missions.

As the story opens, the shuttle carrying one such group of young people to the planet Klydor crash-lands on the planet surface. Most of the teen-agers, held in suspended animation, die in the crash, but five of them survive, as well as the maniacal Lamprey, an ex-government "Crusher" with a lust for power. The five heroes must survive the terrors of both the unknown planet and the threat...