All it took was the recent Spider-Man: Brand New Day teaser to jump start interest in the next chapter of the Marvel Cinematic Universe; as if it was a new concern. Part of that is because of the secrets that continue to creep into the world through official (and unofficial) updates.
Both sides of that coin are present, as a new rumor pertaining to Sadie Sink’s role has me revising my stance on Keith David’s potential MCU introduction, both sides of that coin are covered. Honestly, I think this scenario should have come to my mind sooner, so I don’t want to delay any further in laying out how this still unconfirmed Gargoyles icon might be venturing into the multiverse of madness.

Sadie Sink Just Might Be The MCU’s Jean Grey After All
Online scoopers Jeff Sneider and John Rocha seemed to confirm as much, during a recent installment of their show The Hot Mic. As Rocha prodded his co-host for some deep dish Marvel intel, Sneider dropped that bomb of psychic energy as follows:
I did walk it back, but I’m now here to say it’s true. I hear that she is, in fact,playing Jean Grey. …They want to introduce mutants. Now’s the time. Spider-Man’s essential to the future of the MCU.’
While online scoops are usually worth the paper they’re printed on, I’m actually pulling for that statement to be proven true. We shouldn’t forget the fact that Avengers: Doomsday’s massive cast includes a lot of OG cinematic X-Men making their return. This theoretical passing of the torch to the new age of Mutants is definitely on the horizon, and Sadie Sink’s hypothetical Jean Grey introduction only serves as a logical pivot point.
The clues are already on the board as well! A bunch of random people being mentally controlled by an unknown force in the Spider-Man: Brand New Day trailer sound like potential victims of Ms. Grey’s raw powers. What better way to bid farewell to Patrick Stewart’s Charles Xavier than to have him advise an alternate Professor X in the right way to handle this chaos. Which is exactly the point that leads to my big lightbulb moment involving Keith David. In hindsight, I feel foolish for not landing on the scenario I’m about to propose sooner.

Keith David Could Be The MCU’s New Professor Xavier
I guess I’m truly a fan of the Marvel Cinematic Universe after all, as I am the latest to have fallen for the temptation of Mephisto. Previously I’d guessed that the RIck and Morty voice actor was going to be a devil of an addition to MCU Phase 6; which would trigger an event worthy of the title Brand New Day. Hindsight now has me granting myself half credit, as my new theory deals with a similar shift, just a different day.
I’m now betting my chips on Keith David playing a potential new variant of X-Men’s Professor Charles Xavier! While we shouldn’t consider this hypothetical introduction an end all/be all pivot point to our favorite team of Mutants, a chain of events does seem to be forming to connect this very in demand property as Marvel’s thematic future.

The X-Men Could Be The Bridge Between Spider-Man: Brand New Day And Avengers: Doomsday
There are several ways this new Spider-Man: Brand New Day theory could work to set up the MCU’s inclusion of the X-Men. For starters, Mr. David’s voice-over about a spider’s lifecycle sounds a lot like the sort of wisdom Professor X would give, both in the optimistic tone and the science at work. Pair that with Bruce Banner (Mark Ruffalo) talking about Peter’s DNA “mutating,” and you’ve got another firm brick on the road to the School for Gifted Youngsters.
Now here’s the kicker that pulls it all together: Jean Grey’s introduction in Brand New Day could see her wreaking havoc with her Jean/Dark Phoenix duality. Which would attract the attention of not only Peter Parker, but also Professor Xavier. Another portion of the report cited above seems to lock this theory into place, as Jeff Sneider revealed Jean Grey’s role may have developed further through this twist of fate:
Remember we were hearing those rumors of the older female villain? Those were legit rumors, and I’d heard that basically Anne Hathaway passed, and Sarah Snook passed. Once those two passed, Marvel was like, ‘Hmm. Should we just beef up Jean’s role a little bit?
That could mean that the fourth Spider-Man movie would involve Charles using his powers to put up the mental barriers that keep the Phoenix at bay – setting up the foundation for their backstory as mentor and protege. Naturally these events could widen any multiversal rifts, and faster than you can say “DOOOOOM!”, Robert Downey Jr.’s new baddie would be upon us – requiring the mightiest fighting force to take him down.

The Standard “Marvel Could Prove Me Wrong” Disclaimer
While I’m quite proud of this case I’ve built, it is firmly living in the realm of theory, built on speculation. Before you know it Kevin Feige could come out and definitively debunk the web I’ve just spun; staring in to the camera as if to say, “Sorry, kid.” So let me throw down my own Infinity Gauntlet and brazenly say two words to Mr. Feige: “Your move.”
Should I find myself webbed up by my own hubris, you’ll be able to see the results in the THS Movie News archives. But if I’m right, then I present Marvel Studios with the wager of a Feige-Approved baseball cap as my spoils. In fact, that Fantastic Four one in the image above would do nicely.