"Jet and Mitch travel from Earth to the Moon by rocket. The Mars fleet (the flagship Discovery, 8 freighters and 20 men) begins its journey. During an EVA, Mitch's safety line fails, leaving him adrift. Later Discovery's crew explore the valley's ruined city, but Lemmy vanishes, and experiences a hypnotic dream. He's later found with McClain (pilot of #2), who is now mysteriously able to breathe the Martian air."