A recent rumor regarding Marvel Studios' upcoming Eternals suggests that Namor the Sub-Mariner might be making his debut in the Marvel Cinematic Universe sooner than first thought. But while Namor is an important figure in Marvel Comics and has been teased several times in the MCU, Eternals is not the best place to introduce the character.
To start things off, Namor has little connection to the Eternals. In the comics, Namor McKenzie was the son of a human sea captain and an Atlantean princess, with his enhanced powers such as flight being attributed to the presence of the X-Gene, meaning he is a mutant. This contrasts strongly with the Eternals, who receive their abilities and immortality due to being creations made by the Celestials. And while the Sub-Mariner's comic history has seen him join the X-Men, fight alongside the Avengers, and butt heads with the Fantastic Four, the Eternals were never a group that he had much of a relation with, if any.
On top of that, the sinking city referenced in the rumor might not even be Atlantis, but Lemuria. The small continent of Lemuria is home to the Deviants, who were announced earlier this year as the antagonists of the Eternals. Given that the film will span thousands of years, it's not impossible to think that fans could see the sinking of Lemuria, which was a result of Celestial retaliation over an attack from the Deviants. Though, in the comics, this event, also known as the Great Cataclysm, simultaneously sinks Atlantis as well.
A film that makes more sense for the Sub-Mariner to make his debut -- at least on paper -- is Doctor Strange in the Multiverse of Madness. Marvel Studios President Kevin Feige recently teased the debut appearance of a mystery character in this film. While it could literally be anyone, many clues have been pointing towards Namor, including a now-deleted tweet by Scott Derrickson, the film's former director, sharing the cover of Fear Itself: The Deep #1, a comic which features both Strange and Namor.
If Namor makes his debut in the Doctor Strange sequel, it could be setting him up for a significant role in Black Panther 2. In the comics, Namor's hostile nature has often caused conflict with other heroes, with T'Challa being a prominent opponent. During the 2012 event comic series Avengers Vs. X-Men, Namor, powered by the Phoenix Force, wages war on Wakanda, flooding much of the country with a tidal wave. The addition of Namor as an antagonist in the Black Panther sequel is not only a good way to showcase the undersea king's arrogant character, but can also solve the problem of Black Panther having a weak Rogue's Gallery of villains.
For the mutant king of Atlantis to debut in an already crowded film like Eternals in which he has little to do with the protagonists may be an example of Marvel Studio biting off more than it can chew. Namor's God-like abilities, as well as the mythology surrounding Atlantis, might make his presence seem like a good fit with the rest of the film's heroes, but he ultimately does not belong in the film.
Directed by Chloé Zhao with a screenplay by Matthew and Ryan Firpo, The Eternals stars Richard Madden as Ikaris, Kumail Nanjiani as Kingo, Lauren Ridloff as Makkari, Brian Tyree Henry as Phastos, Salma Hayek as Ajak, Lia McHugh as Sprite, Don Lee as Gilgamesh, Angelina Jolie as Thena, Barry Keoghan as Druig, Gemma Chan as Sersi and Kit Harington as Dane Whitman, aka the Black Knight. The film arrives in theaters on Nov 6.