Earth is an environmental disaster area when humanity gains new hope: a star gate is discovered in the solar system, built by a long-gone alien race. Earth establishes extrasolar colonies and discovers alien races—including the warlike Fallers, the only spacefaring race besides humans. Mysterious, uncommunicative, and relentlessly bent on humanity's extinction, the Fallers have mastered the star gates, and are closing in on earth. Dr. Bazargan commands the scientific team sent to a newly discovered world to study its humanoid natives: beings who literally perceive only one reality. To lie is to be unreal—and condemned to death. The humans must flee for their lives across the unknown planet when they and the aliens learn the scientific mission is a lie. It's the cover for a secret military exploration of the moon Tas, which is another artifact of the gate-makers: a superweapon capable of annihilating all life in a star system, and already known to the Fallers. Nancy Kress has won the Hugo, the Sturgeon, and three Nebula Awards. She is justly acclaimed as a literary SF writer, but receives little acknowledgement that her work is hard SF. Probability Moon should change this, winning her many new readers while pleasing her fans. It's a rare and desirable hybrid: a literary, military, hard-SF novel. Set in the same world as her Nebula- and Sturgeon-winning novelette, "Flowers of Aulit Prison," Probability Moon is the first book of a trilogy, but it has a self-contained story line. The sequel, Probability Sun, will appear in 2001, and the concluding book will be The Fabric of Space. —Cynthia Ward