Comic Title: Action Comics #306
Publisher: DC (National Periodical Publications, Inc.)
Address: 575 Lexington Avenue, New York, NY
Cover Date: November 1963
On Sale Date: September 26, 1963 Newsstand Date September 26, 1963
Source: House Ad, Superman's Girl Friend Lois Lane #45, Page 30

Copyright Date September 26, 1963
Source: Library of Congress, Periodicals 1963

Newsstand Date September 26, 1963
Source: Newsdealer Magazine, V18 #8

Frequency: Monthly
Cover Price: $0.12
Page Count: 32
Editor: Mort Weisinger

Title: "The Maid of Doom"
Pages: 14

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

Writer: Leo Dorfman
Artist: Jim Mooney

Reprinted In:
Adventure Comics #398 (1970)
Showcase Presents Supergirl Vol. 2 TPB (2009)
Supergirl:The Silver Age Omnibus Vol. 1 HC (2016)
Supergirl:The Silver Age Vol. 2 TPB (2018)

Feature Character(s)

• Supergirl (last appearance in Adventure Comics #313; next appearance in Superman's Pal, Jimmy Olsen #73)

Supporting Character(s)

• Edna Danvers (last appearance in Action Comics #305; next appearance in Action Comics #307)
• Dick Malverne (last appearance in Action Comics #305; next appearance in Action Comics #308)
• Streaky (last appearance in Adventure Comics #313; next appearance in Action Comics #309)
• Comet (last appearance in Adventure Comics #313; next appearance in Action Comics #307)

Villain(s)

• Agent Sklor (disguised as Krypto, Streaky, Comet, Mr. Mxyzptlk, and Superman; no further appearances)
• The Plasmos (a warrior race from planet Mutor; no further appearances)

Guest Appearance(s)

• Krypto (last appearance in Superman #165; next appearance in Action Comics #309)
• Superman (last appearance in Action Comics #306; next appearance in Superman's Girl Friend, Lois Lane #45)

Cameo Appearance(s)

• Mon-El (in flashback to the first story of Superboy #89 and the second story of Adventure Comics #305)
• Brainiac 5 (in flashback to the second story of Adventure Comics #305)

Synopsis:
After returning from a mission of peace to three alien worlds, Supergirl’s touch becomes deadly to other super-beings. Streaky and Krypto perish when she touches them, then Comet and even Mxyzptlk are killed. Distraught, Supergirl contacts Superman who exiles her to the Phantom Zone.

Once Supergirl has disappeared, Superman transforms into an alien from the planet Mutor. The alien had impersonated Superman and the other super-beings in order to trick Supergirl. When reporting back to his leaders on Mutor, the alien is startled when Supergirl arrives. She saw through the hoax and created a fake Phantom Zone projector. After outwitting the aliens, Supergirl gets them to agree to a peace treaty with Earth.