For years, fans have campaigned to see the Fantastic Four appear in the MCU. Now, with the release date of Avengers: Infinity War bumped up, some have begun to believe Marvel's First Family will actually appear in the film.

We know the Fantastic Four are coming to the MCU eventually - Disney said as much in the wake of the Fox purchase - which has started speculation they're already here. Some argue that the Fantastic Four were the ones who purchased Avengers Tower in Spider-Man: Homecoming, making it sly foreshadowing. Meanwhile, the cosmic nature of Infinity War is unarguably a perfect place to introduce the team. In May 2017, Stan Lee himself made a throwaway comment that new heroes would be introduced in the movie; his assistant quietly stopped him spilling any further details.

RELATED: Avengers 5 Should Definitely Include The Fantastic Four

Now, these fans claim the evidence is building up. Let's take a look at the facts.

Did The Infinity War Date Change Announcement Contain A Fantastic Four Clue?

The fire has been stoked by the recent announcement that Avengers: Infinity War will release a week earlier. It's not the date change that's had fans speculating, but how Marvel announced it: it was revealed in an amusing Twitter exchange between Marvel's account and Robert Downey Jr.'s. It all led to Marvel announcing a "FANTASTIC" idea.

While U.S. audience celebrated the earlier release, some eagle-eyed users honed in on the use of the word "Fantastic." It was, they argued, a clear nod to the Fantastic Four, an early clue they'd become involved. They scoured for more evidence, including the Infinity War poster potentially hiding a "4" and Marvel's VP & Creative Executive of New Media, Ryan Penagos, tweeting a cryptic gif reading "Imagine what you'll know tomorrow."

Read More: Why Marvel Moved Avengers: Infinity War’s Release Date

If this argument is right, Marvel was teasing the imminent arrival of the Fantastic Four. But that can not be the case. For starters, the logo that allegedly hides a "4" is the same one used throughout the Avengers' history; not just Infinity War's marketing or prior MCU movies, but in the comics as well. Secondly, Penagos doesn't work on the Studios side of Marvel, so wouldn't be involved in a big drop. Although there's a much bigger reason why this won't happen.

The Fantastic Four Aren't Coming To The MCU Anytime Soon

Film rights to the Fantastic Four are traditionally associated with Fox, and Disney is currently in the process of purchasing the bulk of Fox's movie assets. Many fans assume this to be a "done deal", as though the offer has been agreed and the sale has already been completed; the suggestion being that the only barrier to mutants et al in the MCU is time. That isn't quite correct, however: in reality, the purchase is currently sat with the regulators, and won't be approved until late this year at the earliest - more likely partway through 2019. As a result, both Disney and Fox are proceeding as though nothing has changed. Fox has already started development on a range of X-Men movies over the next few years, while they also have a Doctor Doom movie in the works. The Doctor Doom property is, of course, associated with the Fantastic Four - meaning there have been no behind-the-scenes deals only related to the Fantastic Four.

Besides which, it's worth noting the Disney offer was finalized in December. Infinity War was in post-production by that point and its sequel, Avengers 4, had almost finished filming. It would be far too late to add the Fantastic Four into these two movies.

Assuming regulatory approval and Marvel fast-tracking adding the Fantastic Four to the MCU, their arrival is still a few years out; if they begin drafting scripts and hiring production crew the moment the ink's dry, they'll most likely target a release date of 2021 or 2022. Definitely not in April this year.

Related: How Long Until X-Men Join the Avengers?

Forget the fan-theories. The simple fact is that, in the best-case scenario, the Fantastic Four are not about to appear in Avengers: Infinity War. The only real argument is the fact Marvel used the word "FANTASTIC." And, in light of the fact the Disney purchase is still awaiting regulatory approval, that's simply not strong evidence at all. Maybe they're following up the Mini Coke advert by doing a tie-in with Fanta?

Next: Did Infinity War Trailers Already Reveal The Soul Stone?

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