- Script
- Bob Rozakis
- Pencils
- Jack Kirby (pages 1-2, 10-24); Alex Toth (pages 3-9)
- Inks
- Greg Theakston
- Colors
- Greg Theakston
- Letters
- John Costanza
- Genre
- superhero; adventure
- Characters
- Superman; Challengers of the Unknown [Ace Morgan; Rocky Davis; Red Ryan; Prof Haley]; Mr. Jenkins; Jor-El (flashback); Lara (flashback); Zo-Mar (introduction, villain); Phantom Zone inhabitants [General Zod; Jax-Ur]; Miss Bernstein
- Synopsis
- At the Daily Planet, the Challengers of the Unknown seek help to contact Superman to help them solve the mystery of a card with a Kryptonian letter. Superman uses his mind-prober ray to recall Zo-Mar, a Kryptonian criminal shot into space before the discovery of the Phantom Zone, and his mind-slaving card. Superman and the Challs find Zo-Mar, but he enslaves them all with his card. The card, however, inhibits Kryptonian super-powers, and when Superman and the Challs trick Zo-Mar into grabbing the card, they make him weak enough that Superman can knock him out and send him to the Phantom Zone.
- Reprints
- Keywords
- Fortress of Solitude; Phantom Zone
Credits for script, pencils and inks confirmed from Julius Schwartz's editorial records, provided by DC Comics.
Pages 3-9 were originally created as a Challengers of the Unknown story to appear in Adventure Comics (DC, 1938 series) #498.
- Script
- Bob Rozakis
- Letters
- typeset
- First Line of Dialogue or Text
- What made 'A World Full of Supermen' so much fun was not only its connection…
Letters from: Neil Ahlquist, Kevin Lawless, Rick Steel, and Michael Pickens.