On a harsh, remote world, GHENNIT has spent the past three years working as an engineer for the Concord. When one of their transport freighters crashes, a review of the wreckage suggests the vessel to have been the target of a revolutionary energy weapon no one can identify. Ghennit's colleagues believe the Concord's rival, the Aura, has sent an operative to sabotage their work. Ghennit himself knows two pieces of the truth. First, the crashed freighter was not a target of the Aura. Second, the Aura does have a spy among the Concord. It's him. As Ghennit carries secrets that threaten a fragile peace, he searches for answers about a new danger that could enshroud both sides. GRASP OF SHADOWS introduces readers to The Unpromised Worlds, where two rival human factions explore a rich swath of frontier space, balancing exploration and scientific breakthroughs against a precarious, cold war-style peace.