Like its predecessor, The Lost Steersman
(2003), Kirstein's highly entertaining fourth book in her Steerswomen series offers plenty of humor and intrigue while seamlessly blending fantasy and SF. Steerswoman Rowan, who travels the world collecting and disseminating information, has come to Donner to investigate the wizard Kieran, who died 42 years earlier when an orbiting Guidestar, responsible for clearing land for the nomadic Outskirters' herds, fell from the sky. Rowan knows the Guidestar was destroyed by the master wizard Slado, once Kieran's apprentice, but the generation-old issue has now become even more important, because Slado recently used Guidestar magic to destroy three Outskirter tribes. Rowan needs to learn all she can about Slado and his allies—but that means avoiding Donner's current wizard, Jannik, and working with William, a runaway wizard's apprentice who has secrets of his own. Kirstein deftly captures the joy of Rowan's "eureka" moments as she learns to view magical power in a revolutionary way. Especially well done is the scene where she grasps the concept of programming, then proceeds to work out the steps of a list of instructions on dragons to fool a herd of the deadly beasts. This is fiction for readers who appreciate clever world-building and surprises as much as they like action and character. Agent, Frances Collin. (Aug. 31)