A ship, fleeing a dying planet, passes through a portal in hopes of reaching a new world. But they are betrayed by those left behind and are trapped in a space between space, stranded on two tiny worlds separated by only 40 feet. They must fight for generations to survive. 900 years have passed. Erret, and the descendants of those original survivors, have eked out a living on what they call the 'Reef', avoiding death by the planet's strange creatures and topography. The time has come to leave. A new world awaits. But Kristin, the woman he loves, and the rest of the population now consider the Reef home. They refuse to leave. Then the Horde arrives, a voracious species that consumes worlds, and panic sets in. To make matters worse it seems the Reef itself is trying to kill them. Erret must find a way to bridge the 40 feet of dead space to Companion (The Reef's sister planet) and find answers on how to pass through the approaching portal. Success means leaving Kristin behind. Failure means death for all. For Erret, the problems appear insurmountable.