A predicted sequel to The Zero Stone (1968, p. 191, J-73) which again features jewel merchant Vondar and his unusual alien companion, Eet. Here they are still tracking down the origin of the zero stones (that give off an uncanny power) and the search lands them in the den of the Thieves' Guild. Vondar must pose as his own father (a gem appraiser) to keep them alive and as he is tested he discovers a second zero stone among the Thieves' treasure along with an unusual star map that may hold the key to a lost Forerunner civilization. The author's version of hallucinatory and telepathic effects is excellent and the Vondar/Eet duo is inspired. Perhaps they will continue charting stars even after Eet undergoes a final, surprising transfiguration. So far, two of the author's best.