Comic Title: Challengers of the Unknown #5
Publisher: DC (National Comics Publications, Inc.)
Address: 575 Lexington Avenue, New York, NY
Cover Date: Dec/Jan 1958
On Sale Date: October 16, 1958 Copyright Date October 16, 1958
Source: Library of Congress, Periodicals 1958

Frequency: Bi-monthly
Cover Price: $0.10
Page Count: 32
Editor: Jack Schiff

Title: "The Riddle of the Star-Stone"
Pages: 25

Feature(s):
Challengers of the Unknown (of Earth-1)

Writer/Penciller: Jack Kirby
Inker: Wallace Wood

Reprinted In:
Challengers of the Unknown Archives Vol. 2 HC (2004)
Showcase Presents Challengers of the Unknown Vol. 1 TPB (2006)
Challengers of the Unknown Omnibus HC (2012)
Challengers of the Unknown by Jack Kirby TPB (2018)

Feature Character(s)

• Challengers of the Unknown (last appearance in Challengers of the Unknown #4; next appearance in Challengers of the Unknown #6)
• Ace Morgan (last appearance in Challengers of the Unknown #4; next appearance in Challengers of the Unknown #6)
• Rocky Davis (last appearance in Challengers of the Unknown #4; next appearance in Challengers of the Unknown #6)
• Red Ryan (last appearance in Challengers of the Unknown #4; next appearance in Challengers of the Unknown #6)
• Prof. Haley (last appearance in Challengers of the Unknown #4; next appearance in Challengers of the Unknown #6)

Supporting Character(s)

• June Robbins (last appearance in Challengers of the Unknown #3; next appearance in Challengers of the Unknown #6)

Villain(s)

• Vreedl and his thugs (no further appearances)

Other Character(s)

• Professor Brandon (an archaeologist; no further appearances)
• The rajah of Djiizari (no further appearances)

Comments:
Chap. 2: "The Birdman of Djiizari"
Chap. 3: "The Challenge of the Super Creature"

Synopsis:
The Challengers are summoned by June Robbins and archaeologist Professor Brandon. They learn that Brandon's former assistant Vreedl has stolen an artifact that will grant him super powers when four gems are placed upon it.

The Challs chase Vreedl across the globe. At each stop Vreedl captures the gem and gains a new power: first fire projection, then flight and aquatic powers. When Vreedl recovers the final stone, his powers become permanent and he is invincible. However, Ace tricks him into destroying the Star-Stone which gave him his powers. With the stone destroyed, Vreedl loses his powers and is apprehended.