Appearing in "20,000 Leagues Under Justice!"
- Beast (Hank McCoy) (Avengers applicant) (Temporarily impersonates President Rockefeller)
- Moondragon (Heather Douglas) (Avengers applicant)
- President Nelson Rockefeller
- Cadre Cartel (First appearance)
- Squadron Supreme (Main story and recap)
- Hugh Jones (Mentioned)
- Angel (Warren Worthington III) (Mentioned)
- Kingsley Rice's mother (Mentioned) (Unnamed)
- God (Yahweh) (Invoked)
- Mercy General Hospital
- Unnamed nurse
- Dr. Richard Horrigan (Behind the scenes)
- Lord (Yahweh) (Invoked)
- Great Xenon (Invoked)
Races and Species:
- Humans (Main story and recap)
- Synthezoids (Main story and recap)
- Fish (Mentioned)
- Turkeys (Mentioned)
- Multiverse (Main story and recap)
- Other-Earth (Earth-712) (Main story and recap)
- Prime Marvel Universe
- Captain America's Shield
- Doctor Spectrum's Power Prism
- Iron Man Armor Model 3
- Cat Suit
- Serpent Crown
- Tomb Thumb's Micro Module
Synopsis for "20,000 Leagues Under Justice!"
The remaining Squadron Supreme members set out to track down the Avengers and retrieve the Serpent Crown. The Beast and Hellcat team up to defeat the trio of Amphibion, Tom Thumb, and Cap'n Hawk, however, while Iron Man and Captain America best the Whizzer and Dr. Spectrum. Then the Avengers invade the White House itself and locate the device which can return them to their own world. The Beast, disguised as the President, keeps the Squadron occupied, while forcing them to face the fact that their world has been taken over and that, by never questioning their elected officials and corporate leaders, they have been aiding the enemy. Thus, when the Avengers make their escape, the Squadron members decide not to follow them.
- The Beast compares Cap'n Hawk to his old friend and fellow (former) X-Man Angel.
- This issue contains a letters page, Avengers Assemble. Letters are published from Peter Sanderson, Jo Duffy, Bruce Canwell and Vallard Eding.
- As seen on page one, this issue is Story # JV303.
- The issue's title is a nod to the Justice League, on whom the Squadron Supreme is based. The opening splash page, with captioned headshots of all the heroes in the issue, is an homage to the Justice League/Justice Society team-ups of the Silver Age, which often used the same device.