Comic Title: Fantastic Four #6
Publisher: Marvel (Canam Publishers Sales Corp.)
Address: 655 Madison Avenue, New York, NY
Cover Date: September 1962
On Sale Date: June 12, 1962 Copyright Date June 12, 1962
Source: Library of Congress, Periodicals 1962

Newsstand Date June 21, 1962
Source: Newsdealer Magazine, V17 #4

Frequency: Monthly
Cover Price: $0.12
Page Count: 32
Editor: Stan Lee

Title: "Captives of the Deadly Duo"
Pages: 24

Feature(s):
Fantastic Four

Writer: Stan Lee
Penciller: Jack Kirby
Inker: Dick Ayers

Reprinted In:
Fantastic Four Annual #3 (1965)
Mighty World of Marvel #12 (1972)
Mighty World of Marvel #13 (1972)
Marvel Treasury Edition, Featuring the Fantastic Four #2 (1974)
Complete Fantastic Four #12 (1977)
Complete Fantastic Four #13 (1977)
Marvel Masterworks Vol. 2:Fantastic Four Vol. 1 HC (1988)
Marvel Masterworks Vol. 2:Fantastic Four Vol. 1 HC (1998)
Essential Fantastic Four Vol. 1 TPB (1999)
Marvel Masterworks:The Fantastic Four Vol. 1 – Barnes & Noble Edition TPB (2003)
Marvel Masterworks Vol. 2:Fantastic Four Vol. 1 HC (2003)
Marvel Masterworks Vol. 2:Fantastic Four Vol. 1 HC [Variant] (2003)
Fantastic Four Omnibus Vol. 1 HC (2005)
Fantastic Four Omnibus Vol. 1 HC [Variant] (2005)
Marvel Masterworks:The Fantastic Four Vol. 1 TPB (2009)
Marvel Masterworks:The Fantastic Four Vol. 1 TPB [Variant] (2009)
Fantastic Four Epic Collection:The World's Greatest Comic Magazine TPB (2014)
Namor, the Sub-Mariner Epic Collection:Enter the Sub-Mariner TPB (2021)
Mighty Marvel Masterworks:Fantastic Four Vol. 1 TPB (2021)
Mighty Marvel Masterworks:Fantastic Four Vol. 1 TPB [Variant] (2021)
Doctor Doom:The Book of Doom Omnibus HC (2022)
Doctor Doom:The Book of Doom Omnibus HC [Variant] (2022)

Feature Character(s)

• Fantastic Four (last appearance in Fantastic Four #5; next appearance in Fantastic Four #7)
• Mister Fantastic (last appearance in Fantastic Four #5; next appearance in Fantastic Four #7)
• Invisible Girl (last appearance in Fantastic Four #5; next appearance in Fantastic Four #7)
• Thing (last appearance in Fantastic Four #5; next appearance in Fantastic Four #7)
• Human Torch (last appearance in Fantastic Four #5; next appearance in Fantastic Four #7)

Villain(s)

• Doctor Doom (last appearance in Fantastic Four #5; next appearance in Fantastic Four #10)
• Sub-Mariner (last appearance in Fantastic Four #4; next appearance in Fantastic Four #9)

Other Character(s)

• A telegram deliveryman (no further appearances)
• A crowd of spectators (Harry, Pete, Hiram and Matilda named; no further appearances)
• Tommy (a hospitalized boy; no further appearances)

Comments:
Part 2:"When Super-Menaces Unite"
Part 3:"When Friends Fall Out"
Part 4:"Trapped"
Part 5:"The End... or the Beginning?"

This story contains the second mention of "unstable molecules" from which the Fantastic Four's costumes are made. They were first mentioned in Tales to Astonish #35 which was released before this issue.

Synopsis:
Doctor Doom tracks down the Sub-Mariner and proposes an alliance. Namor agrees to the team-up as long as they do not harm Sue Storm. Doom then gives Namor a device to plant inside the Baxter Building. The Sub-Mariner then approaches the Fantastic Four peacefully. While the team decides what to do about Namor, Doom uses his device to lift the Baxter Building into orbit.

Each member of the team tries to reach Doom who is piloting a spacecraft which is magnetically connected to the building. They all fail. Finally the Sub-Mariner succeeds in reaching Doom and taking over the ship. Doom is left on a meteor, while the Baxter Building and all within are returned to Earth. The Sub-Mariner and the Fantastic Four reach an uneasy truce, as Namor returns to the sea.