Fifty years after man reached Venus and Mars, and colonization of both planets began, free enterprise in space was suddenly strangled by the emergence of five giant companies. Employing the most ruthless practices - intimidation, bribery, and political blackmail - they gradually gained a monopoly in the field of commercial space travel.

Crushing everyone in their way with their Gestapo-like tactics, the Five Companies went unthreatened until they outdid even themselves with their cold-bloodedness. Their cloak-and-dagger murder of a noted space researcher sparked an unprecedented challenge by a youthful group of scientists, headed up by brilliant, beautiful, and determined Catherine Rogers and superbly aided by an alien sphere of luminescence....