From the New York Times Bestselling author of the DUNE series comes a spectacular science fiction novel:Billy Jeeling is the greatest hero in the history of mankind, the scientific genius who designed and built Skyship, an immense flying city that has been cleansing and repairing the atmosphere for decades--using his secret technologies. But he's an old man now, and has overstayed his welcome. The one-world government of the AmEarth Empire wants him to step down and turn over his secrets and technologies to them to control. Billy knows this would be most unwise.