Mysterious acts of sabotage against the Third Power, founded by Perry Rhodan, shake the recently achieved peace. A mysterious unknown figure, who calls himself Overhead, has declared war on Perry Rhodan. Overhead possesses hypnotic powers, and one of his strongest weapons is a dangerous mutant. Perry Rhodan and his friends from the mutant corps are so preoccupied with repelling Overhead that the intrusion of foreign space travelers into the Solar System goes almost unnoticed. By the time Rhodan can turn his attention to this new and threatening development, it is almost too late. Perry Rhodan makes young space cadet Julian Tifflor a cosmic decoy to solve the mystery of the strangers. In doing so, he encounters an extraterrestrial power group that seems to have influence in all important areas of the Milky Way. They are the Springers, who have established a galactic trade monopoly. They do not forgive Rhodan for establishing a small trading outpost on Ferrol in the Wegasystem. Before they know it, Perry Rhodan and his friends find themselves embroiled in cosmic disputes.