It is the early 24th century and planet Earth is under blockade, for the solar system was never the empty resource people once believed it to be. It is occupied by others from elsewhere, others with whom the human race now fights the Third Reclamation War. Human space stops at the Ring, a mega-structure encircling the Earth and built out of space-time condensate using technology which may now enable an effective challenge to the alien enemy. A young officer, Paul Strange, joins his regiment at Montgomery base in segment eighteen where, over the subsequent months, he will play a crucial part in the first great deciding battle of the war.