The thrilling adventures of the death - defying Challengers of the Unknown continue, with more astonishing tales from comics' Silver Age. Created by comics legend Jack Kirby, the Challengers are test pilot Ace Morgan, daredevil Ace Ryan, boxing champ Rocky Davis and genius scientist Prof. Haley. Four men who barely survived the crash of a small aircraft, they consider themselves to be living on borrowed time, and dedicated themselves to a life of harrowing adventures. Using their combined skills and knowledge, they traverse the globe, willing to face any danger, and fight any and every astounding obstacle--all in the name of good.