An alien race arrives. Are they here to save humanity or destroy it?
Welcome to the twenty-fifth century.
Joe South, test pilot who’d been lost for five centuries in the unexplored territory known as spongespace, had at last begun to carve a place for himself in this human society that was so different from his own. But he knew, as perhaps no one else did, that the mysterious, seemingly unbreachable Ball — towed insystem by a crazy old scavenger and now floating far too close to Threshold — represented dangers beyond imagining. South had given up trying to tell this to the humans of the United Nationals of Earth, but now things were about to change. Now people would listen and believe. South only hoped it wasn’t already too late.