THRUSH agent L.C. Carson uses an Indian reservation as a front for his plan to assemble a hydrogen bomb, and kidnaps the tribe's chief, High Cloud, to ensure cooperation. Solo arranges for the Chief's daughter Charisma to return, but she ends up being kidnapped along with Solo and Illya, who is disguised as an Indian. Solo and Illya, along with a band of young Indian warriors on Motorcycles, encircle Carson and his men and try to stop them before its too late.