On the Edge of Forever

When Dr. Strange cast a cloaking spell to disguise both himself and Sub-Mariner as ordinary people in Defenders #4 (Volume 3), he took wardrobe advice from Star Trek. The spell logically dressed Sub-Mariner in a stocking cap to cover his pointed ears, much like the hat Mr. Spock wore in The City of the Edge of Forever to cover his similarly pointed ears. Dr. Strange, meanwhile, wore a red, flannel shirt reminiscent of the shirt Capt. Kirk wore that same episode.

Note the reverse symmetry regarding the other color choices: While Kirk's jacket was brown and Spock's hat was blue, Sub-Mariner wore a brown hat and Dr Strange had a blue jacket.

Speaking Volumes

Since newer comics do not include the volume number on the copyright page, as comics of earlier years had, I checked the Marvel Comics Database to see that the latest Defenders series (bringing Iron Fist and Red She-Hulk into the fold) is indeed Volume 4.

Volume 1 was the original run of the Defenders that began in the 1970s, with Dr. Strange, Sub-Mariner, and Hulk as founding members. The Silver Surfer was the first of numerous heroes to unofficially join the non-team.

Because the issue-to-issue numbering stayed consistent, the series remained Volume 1 even when the title changed to the New Defenders (issues #125-152).

Volume 2 was most notable for giving Samantha Parrington a chance to reprise the role of Valkyrie and work with the Defenders. In this twelve-issue limited series from 2001, she shared the spotlight with six of the most recognized members of the team: Nighthawk, Dr. Strange, Sub-Mariner, Silver Surfer, Hellcat, and Hulk.

Volume 3 brought back Dr. Strange, Sub-Mariner, Hulk, and Silver Surfer for a dimension-hopping limited series. The ever-dreaded Dormammu was the group's primary adversary during this five-issue adventure from 2005.

Series with variant titles (including Secret Defenders and Last Defenders) were each published as Volume 1 in their own right.