Comic Title: Action Comics #267
Publisher: DC (National Comics Publications, Inc.)
Address: 575 Lexington Avenue, New York, NY
Cover Date: August 1960
On Sale Date: June 30, 1960 Newsstand Date June 30, 1960
Source: House Ad, Superman Annual #1, Page 60

Copyright Date June 30, 1960
Source: Library of Congress, Periodicals 1960

Frequency: Monthly
Cover Price: $0.10
Page Count: 32
Editor: Mort Weisinger

Title: "The Three Super-Heroes"
Pages: 13

Feature(s):
Supergirl (of Earth-1)

Writer: Jerry Siegel
Artist: Jim Mooney

Reprinted In:
Action Comics #334 (1966)
Adventure Comics #492 (1982)
Legion of Super-Heroes Archives Vol. 1 HC (1991)
Supergirl Archives Vol. 1 HC (2001)
Showcase Presents:Legion of Super-Heroes Vol. 1 TPB (2007)
Showcase Presents:Supergirl Vol. 1 TPB (2008)
Supergirl:The Silver Age Omnibus Vol. 1 HC (2016)
Supergirl:The Silver Age Vol. 1 TPB (2017)
Legion of Super-Heroes:The Silver Age Omnibus Vol. 1 HC (2017)
Legion of Super-Heroes:The Silver Age Vol. 1 TPB (2018)

Feature Character(s)

• Supergirl (last appearance in Action Comics #268; next appearance in Action Comics #268)

Guest Star(s)

• Legion of Super-Heroes (last appearance in Legion of Super-Heroes #295; next appearance in Adventure Comics #282)
• Cosmic Boy (last appearance in Legion of Super-Heroes #295; next appearance in Adventure Comics #282)
• Saturn Girl (last appearance in Legion of Super-Heroes #295; next appearance in Adventure Comics #282)
• Lightning Lad (last appearance in Legion of Super-Heroes #295; next appearance in Adventure Comics #282)
• Chameleon Boy (next appearance in Adventure Comics #282)
• Invisible Kid (first appearance; last appearance in Superboy #176; next appearance in Adventure Comics #247)
• Colossal Boy (first appearance; last appearance in Legion of Super-Heroes #295; next appearance in Adventure Comics #282)

Guest Appearance(s)

• Superman (last appearance in Action Comics #268; next appearance in Superman's Pal, Jimmy Olsen #47)
• Star Boy (Thom Kallor; joins the Legion behind-the-scenes; last appearance in Legion of Super-Heroes #306; next appearance in Adventure Comics #282)

Other Character(s)

• An unnamed bus driver and some children (no further appearances)

Comments:
For some unexplained reason, the Legionnaires identify themselves as the sons and daughters of the original Legion members in this story. They also erroneously claim that all members inherited their powers from their extraterrestrial parents.

The Legion’s 18-year-old age limit for new members is first mentioned in this story.

When Supergirl is refused membership in this story, Cosmic Boy mentions that "someone else" has been admitted in her place. Contrary to the account in Secrets of the Legion of Super-Heroes #1, this new member is not Chameleon Boy, who is already a member in this story. By process of elimination, the member in question can only be Star Boy.

Synopsis:
In events paralleling (and from the Legion’s point-of-view, preceding) the initiation of Superboy, the Legion of Super-Heroes approaches Supergirl for membership, and brings her to the 30th century. There, she proves her worthiness by creating a trans-Earth tunnel that will lighten air traffic. Unfortunately, in doing so she encounters a piece of Red Kryptonite that temporarily transforms her into an adult. She is refused membership on the grounds that she now exceeds their 18-year-old age limit.

Heartbroken, Supergirl is forced to return home and wait for the transformation to end, and to wonder if she'’l have another chance at Legion membership.