Comic Title: Showcase #11
Publisher: DC (National Comics Publications, Inc.)
Address: 480 Lexington Avenue, New York, NY
Cover Date: Nov/Dec 1957
Approx. On Sale Date: September 17, 1957 Copyright Date September 15, 1957
Source: Library of Congress, Periodicals 1957
Until 1958 DC did not report actual on sale dates to the copyright office
The publication dates listed in LoC records are NOT release dates.

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

Title: "The Day the Earth Blew Up"
Pages: 24

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

Writer/Artist: Jack Kirby

Reprinted In:
Challengers of the Unknown #80 (1973)
Essential Showcase 1956-1959 TPB (1993)
Challengers of the Unknown Archives Vol. 1 HC (2003)
Showcase Presents Challengers of the Unknown Vol. 1 TPB (2006)
Challengers of the Unknown Omnibus HC (2012)
Showcase Presents:Showcase Vol. 1 TPB (2012)
Challengers of the Unknown by Jack Kirby TPB (2018)

Feature Character(s)

• Challengers of the Unknown (last appearance in Showcase #7; next appearance in Showcase #12)
• Ace Morgan (last appearance in Showcase #7; next appearance in Showcase #12)
• Prof. Haley (last appearance in Showcase #7; next appearance in Showcase #12)
• Red Ryan (last appearance in Showcase #7; next appearance in Showcase #12)
• Rocky Davis (last appearance in Showcase #7; next appearance in Showcase #12)

Villain(s)

• The Tyrans (Garnat and General Tolek named; no further appearances)

Other Character(s)

• Carl Jackson and Warren Moss (Antarctic explorers; no further appearances)

Comments:
Chap. 2: "The Tyrans"
Chap. 3: "The Thing That Came Out of the Sea"
Chap. 4: "One Minute to Doom"

Synopsis:
The Challengers of the Unknown have been called in to locate two missing scientists in the Antarcitc. Following a blizzard Ace and Rocky fall into a crevasse and encounter a giant tube. Prof. and Red are captured by aliens called the Tyrans. Ace and Rocky end up captured as well and are thrown in with the other Challs and the missing scientists.

The Challs manage to hypnotize Garnat, one of the Tyrans. The alien helps them escape. The Challs also learn of the aliens’ plan to tear a large mass of the Earth away with huge explosions. Ace and Rocky stay behind with the scientists to destroy the detonator, while Prof. and Red are teleported back to Washington to disable the bombs.

Ace and Rocky are cornered by the Tyrans, but the scientists help out by releasing heat from the Earth’s core which destroys the detonator and the Tyran base. Prof. disables one of the Tyran’s undersea bombs fearing they will activate in manually. With the bomb disabled the Tyrans use giant machines to attack the coastline, Red manages to destroy the machines with chemical weapons. The Challs in the antarctic return and the remaining Tyrans are mopped up.