Dick Seaton and Marc DuQuesne are the deadliest enemies in the Universe--their feud has blazed among the stars and changed the history of a thousand planets. But now a threat from outside the Galaxy drives them into a dangerous alliance as hordes of strange races drive to a collision with Mankind! Seaton and DuQuesne fight and slave side by side to fend off the invasion--as Seaton keeps constant, perilous watch for DuQuesne's inevitable double-cross!