Comic Title: Challengers of the Unknown #75
Publisher: DC (National Periodical Publications, Inc.)
Address: 909 Third Avenue, New York, NY
Cover Date: Aug/Sep 1970
On Sale Date: June 2, 1970 Newsstand Date June 2, 1970
Source: House Ad, Flash #199, Page 18

Copyright Date June 2, 1970
Source: Library of Congress, Periodicals 1970

Frequency: Bi-monthly
Cover Price: $0.15
Page Count: 32
Editor: Murray Boltinoff

Title: "Ultivac Is Loose"
Pages: 25

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

Writer/Artist: Jack Kirby

Reprinted From:
Showcase #7 (1957)

Feature Character(s)

• Challengers of the Unknown (last appearance in Showcase #6; next appearance in Showcase #11)
• Ace Morgan (last appearance in Showcase #6; next appearance in Showcase #11)
• Rocky Davis (last appearance in Showcase #6; next appearance in Showcase #11)
• Red Ryan (last appearance in Showcase #6; next appearance in Showcase #11)
• Prof. Haley (last appearance in Showcase #6; next appearance in Showcase #11)

Supporting Character(s)

• June Robbins (joins the Challengers as a honorary member; next appearance in Challengers of the Unknown #1)

Villain(s)

• Felix Hesse and Floyd Barker (Ultivac’s creators; no further appearances)
• Ultivac (a living computer; next appearance in DC Comics Presents #77)

Comments:
June is incorrectly shown with dark hair in this story.

Synopsis:
Felix Hesse, a war criminal, and Floyd Barker have created a living computer named Ultivac. Hesse asks the Challengers for help when the robot resists control. The Challengers agree to help, but Hesse is abucted out from under them. Ultivac creates Hesse doubles to act as agents in retrieving materials for him.

The Challengers enlist the aid of robotics specialist, Dr. June Robbins. Red and June trail one of the Hesse double back to Ultivac’s headquarters. June befriends Ultivac which allows Red, Hesse, and Barker to overcome Ultivac.

Rather than turn Ultivac over to the government, Hesse and Barker try to use Ultivac for their personal gain. Ultivac breaks loose and take June with him. He creates a double of himself which is destroyed by the Challengers, but June convinces him to meet humanity half way and work with them.

At a public hearing, an angry Hesse blasts Ultivac and kills Rocky in the process. Rocky is revived from the dead and Ultivac is converted into a immobile computer. June has earned the right to become a Challenger and joins the team.