In the “universe next door” first introduced in S. M. Stirling’s The Sky People, aliens terraformed Mars (and Venus) two hundred million years ago, seeding them with life-forms from Earth. Humans didn’t suspect this until the twentieth century. Then American and Soviet probes landed on our sister worlds and found life—intelligent life, at that. By the year 2000, all the great powers of Earth are contending for influence and power amid the newly-discovered inhabitants of our sister planets. In A.D. 2000, Jeremy Wainman is an archaeologist who has achieved a lifelong dream; to travel to Mars and explore the dead cities of the Deep Beyond, searching for the secrets of the Kings Beneath the Mountain and the fallen empire they ruled. Teyud za-Zhalt is the Martian mercenary the Terrans hire as guide and captain of the landship Intrepid Traveler. But she conceals a secret—one that links her to the enigmatic Ancients, the Lords of Creation who reshaped the Solar System in the time of the dinosaurs. When Jeremy and Teyud meet, the foundations of reality will be shaken—from the lost city of Rema-Dza to the courts of the Crimson Kings.