Marvel fans think they've spotted a huge story spoiler in The Marvels' new TV spot

Potentially big spoilers follow for The Marvels.

A new teaser for The Marvels has landed online – and it's sent Marvel fans into a frenzy over a potentially big story spoiler.

Ordinarily, TV spots for Marvel's upcoming movies and Disney Plus shows don't give too much (if anything) away. The Disney subsidiary likes to keep its plot-based cards close to its chest, so fans can enjoy the Easter eggs, cameos, and other surprises in theaters.

Marvel, though, as seemingly thrown that mantra out of the window with The Marvels' new TV spot. The 15-second teaser, titled 'What Comes Next', was released yesterday (October 31) and it's spawned a wild but credible theory among the Marvel Cinematic Universe's (MCU) devote fanbase.

You can watch the TV spot below, but be warned: we'll be discussing those spoiler-filled fan theories in the next section. If you want to watch the Marvel Phase 5 movie with no idea of what's in store, turn back after you've streamed the video.

The first notable spoiler concerns a line uttered by Monica Rambeau, who reveals there's a "different reality bleeding into ours". This shouldn't come as a surprise – after all, Phases 4, 5, and 6 of the MCU are collectively known as the Multiverse Saga. Some films and TV shows in Phases 4 and 5 have already focused on the Marvel multiverse, including Doctor Strange 2, Loki season 2, and Spider-Man: No Way Home, so MCU fans are accustomed to Marvel's take on the multiversal concept.

However, fans didn't expect The Marvels to reference the multiverse, let alone include it as a major plot thread. Given Monica Rambeau's comment about a forthcoming Incursion – the MCU's term for two universes merging together – though, fans (including Reddit user schrodingersdemet) believe The Marvels has ties to the MCU's overarching multiverse narrative.

But wait, there's more. The TV spot also comes equipped with a tagline "Be there for what comes next", with the text interspersed among the teaser's quick-cut scenes. Usually, this wouldn't be worth poring over but, at the 0:11 mark, the 'X' in 'next' lingers on the screen for a split-second longer than the rest of the text.

Unsurprisingly, fans have immediately come to the same conclusion: the drawn-out 'X' means that the X-Men (or, at the very least, one or two of them) will make their long-awaited MCU debut in The Marvels.

That might seem farfetched, but there's evidence to back it up. First, Professor X – the X-Men's leader – has already appeared in the MCU (albeit as someone from another multiverse) as the Illuminati's leader in Doctor Strange 2. Next, Kamala Khan/Ms Marvel, who'll play a starring role in The Marvels, was revealed to be some form of mutant in Ms Marvel's season 1 finale. In the comics, mutants are humans who possess the X-gene, which grants them superhuman abilities. Anyone who has the X-gene usually (but not always) winds up becoming an X-Men team member (or villain). If Kamala has the X-gene in the MCU, that would make her a mutant and link her to the X-Men.

Then there's the rumor, which emerged last weekend (October 28-29), about one of the film's post-credits scenes referencing the X-Men. We won't spoil it here but, if it's true, the X-Men's gradual introduction to the MCU will continue.

If – remember, this is all fan speculation at this stage – The Marvels does reference the X-Men, it'll act as a primer for Deadpool 3's full introduction of the supergroup. 

The threequel, which is slated to be one of 2024's new movies, will see Ryan Reynolds' Merc With a Mouth team up with Wolverine, who'll be played by Hugh Jackman for one final time. Right now, we don't know if this version of Wolverine will be the same one from Fox's now-defunct X-Men universe (read our X-Men movies in order guide for more details). If it is, though, we could see other mutants from Fox's X-Men films have supporting roles, or at least make intriguing cameos, in Deadpool 3.

Of course, The Marvels' TV spot could be a whole lot of nothing. With its main cast unable to promote the movie due to the ongoing actors strike, Marvel has to get creative with the flick's marketing campaign. Posting a TV spot that teases the X-Men's potential appearance in The Marvels has gotten fans excited about such a prospect, which will surely lead to a ticket sales boost ahead of its theatrical release. 

Redditor REQ52767 suggests this could be a ploy by Marvel to get bums on seats, and the studio would have to deal with the inevitable backlash if the X-Men don't show up. Marvel will claim it meant no harm if that happens – after all, fans wrongly theorized that Loki season 2 would introduce the X-Men, although Loki's second season could also have ties to Deadpool 3. 

Still, with the X-Men's official MCU arrival years away at this point – journalist Devin Faraci claims Marvel can't legally use the X-Men until its contract with Fox expires in 2025 – MCU fans will their new theory The Marvels will come to pass, even if it's not the full X-Men reveal they're craving.

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