Written by Jack Kirby, Dave Wood and Ed Herron. Art by Kirby, Bob Brown, Wally Wood and others. Cover by Kirby. Collecting Showcase Presents #6, 7, 11, 12 and Challengers of the Unknown #1-18 (1957-1959)! Relive the classic Silver Age adventures of Jack Kirby's Challengers of the Unknown - a team brought together by fate dedicated to a life of harrowing adventure in the name of good!