Murdoc finds phenomenal powers in the stone ring that he inherits from his father but only comes to understand those powers completely through contact with an interplanetary wanderer in the form of a feline mutant.

The Zero Stone…that most priceless of alien artifacts, had been the death of Murdoc Jern’s father, and might soon become the ruin of Murdoc himself. It was the Zero Stone which had led him into a partnership with the catlike alien, Eet. And it had been the Zero Stone that had seen them caught as pawns between the Thieves’ Guild and the interstellar force of law, the Patrol. And while Murdoc and Eet had somehow survived against all the odds – had even wrested enough credits from the Patrol to legally buy a spaceship – their troubles were only beginning. For now they must seek their fortune along the uncharted fringes of inhabited space in a search for the world from which the Zero Stone had originally come. But others, too, sought this place which hid treasures beyond imagining. And these unknown rivals, as well as the Guild and the Patrol, were only too ready to sacrifice one insignificant human and his alien ally if they got in the way…