Princess Ardala returns to Earth with a deadly space weapon that can destroy every city on the planet. She informs the Defense Directorate that she will proceed unless Buck Rogers is turned over to her so that she can marry him. Dr. Huer initially refuses but when things look bleak, Buck departs to find a Draconian defector who lives in seclusion on Earth and knows the layout of Ardala's flagship. Unfortunately, the man is insane with the fear of being captured and the only way to learn what he knows is to probe his mind. Meanwhile, Buck goes along to Ardala's flagship to prepare for the wedding and attempts to destroy Ardala's weapon before he becomes her groom.
—Woodyanders