More than a month after its theatrical release, Spider-Man: No Way Home continues to set records in theaters and create anticipation for the upcoming Doctor Strange In The Multiverse of Madness.
This movie has so many possibilities to pull in characters and storylines from other Marvel sources (MCU, comics, Sony, Fox, etc.) so fans have had a blast coming up with theories. Some theories are plausible and rooted in other MCU sources and others are completely wild, seeming to come out of nowhere.
Wanda Is The Villian
Starting with the most realistic theory from @Consistent_Coffee522, "I think Wanda will start off as the villain and then switch sides." Following the events of Spider-Man: No Way Home, Doctor Strange continues to face the fallout of his spell and seeks out Wanda Maximoff for her help closing the rifts in reality.
This idea sees Wanda hearing the voices of her children calling to her from an alternate universe. Instead of closing the last few rifts, she begins frantically opening new ones to find the boys. Doctor Strange tries to stop her but Wanda is too powerful and it leads to a fight before she ultimately does the right thing.
Mutants Are Introduced
This theory builds on the previous one. After Wanda opens additional rifts, a stowaway group of mutants from an alternate universe emerges into the Earth 616 reality. This theory from @kon-el99 suggests that "two Fox X-Men actors [are] rumored to return as X-Men '97 variants," including Sophie Turner's Phoenix and James McAvoy's Professor X.
In this theory, Pheonix fights with Wanda and then Professor X intervenes. Professor X locates Tommy and Billy and uses his telepathy to calm Wanda down enough to restore each reality. The retconned characters return to their original dimensions but Billy and Tommy stay. The widespread use of Wanda's chaos magic throughout the movie creates new mutants in the 616 reality that begin to surface in a later movie or a Disney+ series. This movie seems like the most likely way to bring mutants into the MCU after so many hints in WandaVision and has the potential to be a huge crowd-pleaser.
Christine Becomes The Night Nurse
Christine Palmer becomes the Night Nurse in the comics. Fans suspect the upcoming movie will be the perfect opportunity to introduce her in this capacity and it totally makes sense! Reddit user @madmaxx2 suggests that "the movie will have a scene where the hospital is overflowing with superheroes from the multiverse and Palmer will be responsible for treating them." As an insider on Doctor Strange's new abilities, she will know the importance of keeping heroes' secret identities safe.
This theory means that the Earth 616 reality will be completely flooded with heroes and villains from other realities, to a greater extent than Spider-Man: No Way Home. The trailer reveals Christine getting married and it appears that it is Strange Supreme who is in attendance.
Strange Supreme Becomes An Ally
Strange Supreme is a version of Doctor Strange confirmed to appear in the upcoming movie. This theory is a follow-up to the events that occurred in the Disney+ series, What If making it more likely than others. In the Doctor Strange episode, Christine dies in the car crash and Doctor Strange learns dark magic to bring her back, therefore becoming Supreme Strange.
This results in a series of horrible events and Reddit user @comrade batman's theory states that the upcoming movie will provide Supreme Strange with the opportunity to travel to other realities to make up for these mistakes and protect the multiverse. @comrade batman says, "although the trailer frames him as a new threat to the main Doctor Strange and his universe, I don't think that's the full picture." Strange Supreme and Doctor Strange may square off at first but then will become allies who fight together against the main threat of the movie.
Shuma Gorath Chasing America Chavez Through Dimensions
There are many theories about who will be the villain in Doctor Strange in the Multiverse of Madness. One theory from @simplesMTC places Shuma Gorath as the main antagonist. The theory states that Shuma Gorath, a green tentacled cyclops alien, will be chasing after America Chavez through the multiverse "because he wants her powers to have complete control of the multiverse."
America's powers include the ability to kick open star-shaped holes into different realities to travel across the multiverse. Shuma Gorath is omnipotent so it will be difficult for Chavez to outrun him and he will be more than an equal match for Doctor Strange. Shuma Gorath appears in the trailer and it fits in nicely with America Chavez so this could be a good candidate for a winning theory.
Defender Strange Connected To Tobey Maguire's Spider-Man
With Sam Raimi directing this movie, reddit user @apprehensive-neat-68 has proposed that the film will take place in the Raimi spider-verse. @apprehensive-neat-68's theory states that "Defender Strange is part of The Defenders, a team of superheroes that Tobey Maguire's Spider-Man forms after the ending of Spider-Man: No Way Home" when he returns to his reality with a renewed sense of teamwork.
The Defenders team includes Daredevil, Hulk (Norton or Bana), Namor, Black Cat, Helstrom, and Defender Strange. The Defenders enter Earth 616 through one of the rifts that remain or are opened. Although the theory of Defender Strange entering the movie is confirmed, bringing the whole team in this movie may introduce too many new characters at once that don't have a history in the MCU or an obvious immediate future.
Doctor Doom And The Fantastic Four Appear
Many fans have been fan-casting Doctor Doom and are eager to see him in upcoming projects, including Doctor Strange in the Multiverse of Madness. The comic version of the character has strong ties to the mystic arts which would potentially make him a rival for Doctor Strange. Most fans prefer for him to be introduced as a minor or neutral character if he appears in.
Reddit user @petros_ says, "I think it would be interesting that if he learned magic, it would be from the sorcerers from the London Sanctum since that would be closest to Latveria." He could then encounter the Fantastic Four as the multiverse is opened up. This would lay the groundwork for the future Fantastic Four franchise. Fans are really hoping to see John Krasinski roll up as Reed Richards. Although this would be an exciting storyline, it may be too big of a movie to cram in such highly anticipated characters.
Tom Cruise As Iron Man
Although Tom Cruise has disproved the internet legend that he was originally cast as Iron Man, fans are eager to see him in the role in Doctor Strange in the Multiverse of Madness. This would be one of the biggest cameos in Marvel history.
Redditor @Phunk87 suggests that "Tom Cruise will play a superior Iron Man variant who will be an antagonist and part of the Illuminati." A fight between Iron Man and Doctor Strange would be an epic toss-up as both characters have significant powers and intelligence. If Tom Cruise does appear as Iron Man, he would need to be a significant departure from the great story arc and ending the MCU gave to Robert Downey Junior's character.
Doctor Strange is a Skrull
A less likely theory proposed by @JhonC18 is that Doctor Strange is secretly a Skrull. @JhonC18 reminds folks that "in the new comics Dr. Strange loses his magic and travels to a Skrull planet to forge a new time stone." Other fans have mentioned that the Doctor Strange from Spider-Man: No Way Home was somewhat off and have said the same about his appearances in trailers.
This theory argues that a Skrull could be posing as Strange to destabilize earth enough to invade. This would set the MCU up for the upcoming Secret Invasion series.
Christine Palmer Is The Invisible Woman From Another Dimension
Provided by Reddit user @Orchard101, this theory says "Christine Palmer is secretly from an alternative universe and is Invisible Woman and she is marrying Mister Fantastic. Thus bringing Fantastic Four into the MCU." She could work with America Chavez in her off-hours traveling through the multiverse. As the invisible woman, she could potentially sneak through different realities to help Doctor Strange put different timelines back in order.
She would be the perfect character to do this because she would not cause further disturbances by catching attention. This theory seems highly unlikely and is straight-up weird because there have been no indicators of this in the past. It would be more realistic to cast a new character for this role in the movie.