The Forbidden Borders—an unassailable gravity-powered barrier—confines rival human empires to a few star systems, leaving them to strive endlessly against one another for domination. Now the long-dreaded final war between Rega and Sassa, the last surviving empires, has been fought, and Staffa kar Therma, Lord Commander of the Companions, the finest of mercenary soldiers, is struggling to keep what remains of human civilization alive long enough to find a way to break free of the alien-created Forbidden Borders.