Comic Title: Action Comics #262
Publisher: DC (National Comics Publications, Inc.)
Address: 575 Lexington Avenue, New York, NY
Cover Date: March 1960
On Sale Date: January 28, 1960 Newsstand Date January 28, 1960
Source: House Ad, Adventure Comics #270, Page 15

Copyright Date January 28, 1960
Source: Library of Congress, Periodicals 1960

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

Title: "Supergirl's Greatest Victory"
Pages: 12

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

Writer: Otto Binder
Artist: Jim Mooney

Reprinted In:
Superman Family #167 (1974)
Supergirl Archives Vol. 1 HC (2001)
Showcase Presents:Supergirl Vol. 1 TPB (2008)
Supergirl:The Silver Age Omnibus Vol. 1 HC (2016)
Supergirl:The Silver Age Vol. 1 TPB (2017)

Feature Character(s)

• Supergirl (last appearance in Action Comics #261; next appearance in Superboy #80)

Guest Star(s)

• Superman (last appearance in Action Comics #262; next appearance in Superman #136)

Supporting Character(s)

• Miss Hart (last appearance in Action Comics #261; next appearance in Action Comics #263)
• Mr. Dixon (last appearance in Action Comics #258; next appearance in Action Comics #263)

Other Character(s)

• Two metal eating creatures and their child (no further appearances)

Cameo Appearance(s)

• Zor-El (in flashback to Supergirl’s origin)
• Allura (in flashback to Supergirl’s origin)

Comments:
Supergirl’s skirt is colored red on the cover of this issue.

Supergirl’s origin is recapped in this story, and Superman’s is briefly related as well.

Synopsis:
While helping children at the orphanage, Supergirl spots a kryptonite meteor land in the forest. She decides to try and build up an immunity to kryptonite by gradually exposing herself to it.

She visits Superman at his Fortress of Solitude to tell him her idea. Superman believes the experiment is too dangerous. He shows her the rest of his fortress, including two metal eating creatures. One of the creatures escapes momentarily but is quickly caught.

Supergirl decides to do the experiment anyway. Using the meteor in the woods, she gradually exposes herself to it. Each day she can approach the meteor a little further.

Superman watches her progress from the Fortress. He also stumbles across an underground tunnel. Inside the strange tunnel, he encounters another kryptonite meteor. Supergirl sees him in trouble and comes to help. Believing herself immune she approaches the meteor but it weakens her too. Together with the last bit of their remaining powers the cousins manage to free themselves.

Supergirl’s apparent immunity was caused because the escaped metal eater had laid an egg. The egg hatched and the creature burrowed a tunnel to the forest cave where Supergirl had stored the meteor. The creature slowly ate the kryptonite from the inside which allowed Supergirl to approach it.