MCU's Phase 4 made an astonishing beginning with the integrated Disney+ series WandaVision, which has created several unique theories regarding the future of MCU. On the movies' end, Phase 4 is still set to begin with Black Widow being constantly delayed due to the COVID-19 pandemic. But the most exciting and probably the most significant entry in MCU Phase 4 will be the unofficially titled Spider-Man: Homecoming 3, currently dubbed as Untitled Spider-Man: Far From Home Sequel.

While Spider-Man: Far From Home concluded Phase 3 of MCU, it left the fate of the wall-crawling teenage superhero on a cliffhanger, with his identity publicized by Mysterio at the end. Moreover, Mysterio also managed to blame Spidey for all his crimes, and thanks to J. Jonah Jameson (which marked J.K. Simmons' surprise reprisal of the role), Spider-Man will be a "menace to society" by the time the sequel drops in theaters.

But, the announcement of an old enemy's return in the form of Jamie Foxx's Electro has made Spider-Man 3 more interesting and fascinating. Foxx previously played Electro in Sony's The Amazing Spider-Man 2 which starred Andrew Garfield as Spider-Man; however, things will be different this time. For starters, the now-deleted picture Foxx shared to confirm his involvement in the project showed three Spidermen gazing at a horrifying Electro figure in the sky. That one picture has led fans to speculate the introduction of multiverses in the MCU, with all the previous live-action Peter Parkers collaborating to take on the common enemy. And if that's not enough to hit the nerves, Alfred Molina is set to return as Otto Octavious/Dr. Octopus from Sam Raimi's Spider-Man 2, which starred Tobey Maguire as Peter Parker. So, two villains from two earlier Spider-Man franchises sounds like a "worldly interconnection".

Marvel Studios head Kevin Feige has been advocating to make MCU more immersive and expand it exponentially, with multiverse concept as the center point of that vision. He fixated on the interconnection of Marvel storylines quite a lot many times during the Marvel slate reveal at Disney Investors Day last year. With the announcement of Doctor Strange in the Multiverse of Madness and benedict Cumberbatch's confirmed casting as Doc Strange in the upcoming Spider-Man film, we are definitely set to witness more than one MCU world. And Spider-Man 3 can be the film that blows up that expansion.

It's only logical for Kevin and Marvel to execute multiverse within the MCU as Sony's Spider-Man: Into the Spiderverse has already proved that it's a fan-favorite and widely accepted storyline, which can further the business interests of Marvel Studios. The rights to Spider-Man character are with Sony, which almost led to the cancellation of the Marvel-Sony collaboration of Tom Holland's Spider-Man films. As multiverse can allow the inflow and outflow of Marvel characters from different universes, it can also solve Spider-Man's ownership issues and ensure Holland's portrayal in films across MCU and Sony's Universe of Marvel Characters. A connection between these two franchises may be established in the upcoming Morbius movie, which will also star Michael Keaton probably reprising his role as Adrian Toomes/Vulture from Homecoming (Sinister Six vibes?).

Besides, the situation Tom Holland's Spider-Man is left in calls for some help, and who better than those who already fills his shoes in different dimensions can understand his troubles. Spider-Man 3 will not just have Peter Parker struggling with his dual life, but will now force him to protect his loved ones who are exposed after his identity reveal. There is a slight possibility that the supreme wizard Doctor Strange could help Peter Parker with this issue, but he is surely going to face some serious troubles before he is met with a solution to his problem, especially when some criminals like Mac Gargan, earlier seen in Homecoming (who also is the alter ego of Scorpion in the comics) are after Spidey's life.

On a much larger scale, the significance of Spider-Man 3 is boosted with some other casting confirms. For instance, Jacob Batalon aka Ned Leeds' new weight loss is implying his character's transformation into Hob Goblin just like the comic books. Also, Tobey Maguire has reportedly participated in a costume testing experiment, indicating his reprisal. There were early rumors of Emma Stone, Kirsten Dunst, and Andrew Garfield joining in the rest of the cast, but those have been debunked since then. However, the presence of Garfield and Maguire (which seems likely as their nemesis from respective series is in the film already), will grant a canonical storyline of multiple universes, established in retrospect, thus, encompassing multiple characters from different Marvel properties under one roof.

Moreover, it's reported that Charlie Cox has also shot some scenes as Matt Murdock/Daredevil, a character he plays in the now-canceled Daredevil series on Netflix. Cox's presence will further link the Marvel television storylines more prominently with the MCU films. Earlier, James D'Arcy has reprised his role as Edwin Jarvis from Agent Carter in Avengers: Endgame, marking the first visual nod to the shared continuity between Marvel's films and television productions.

The idea of a multiverse and the star-studded ensemble will make Spider-Man 3 more than just a Spider-Man film. It will help Marvel explore not just multiverses, but would be able to do justice to several character arcs with comic-like accuracy while connecting the dots between multiple cross-shared franchises and their individual storylines. Evan Peters' cameo as a "recast" Pietro Maximoff in WandaVision has also set a probable beginning of inter-universe alliance of Marvel characters, starting with the mutants.

As Tom Holland has dubbed Spider-Man 3 as the "most ambitious film ever made", we are much eager to see what all possibilities can this film bring in Phase 4 of the MCU. Spider-Man 3 will be directed by Jon Watts and is slated to release on December 17, 2021, while a fourth film is in development as well.