There are those whose bodies are too damaged by heredity, disease, or catastrophic accidents to survive outside a mechanical support system. When one of them becomes a shellperson, they choose to strap on a spaceship, and roam the universe with a powerful starship for a body. Bright and spunky Tia was afflicted a mysterious neural disorder. Now she searches for the cause -- to put a stop to it. And Carialle and her partner Keff are explorers who have found an inhabited world with very friendly aliens. Unfortunately, the planet has secret rulers who are anything but friendly....