Dare Chin, responsible for the safety of the Martian Plaque the priceless artifact which proves that intelligent beings existed on Mars a billion years ago; and Dr. Morland, a visiting scientist to the Labyrinth City of Mars interested in experimenting on the plaque; are both found dead and the plaque stolen. Sparta alias Inspector Ellis Troy is sent on an interstellar hunt to retrieve the plaque and trace the killers. Will she be able to overcome the life-threatening pain she frequently experiences and the evil designs of the killers, is the ultimate question?