Top 20 MCU Theories That Turned Out to Be True

“Agatha All Along” (2024)
Ever since we found out about the “Agatha” spinoff show, many fans speculated on who Joe Locke’s character would be. Marvel themselves kept that identity a mystery for a little bit too by only having him be referred to as Teen in early episodes. But most people theorized that Teen was actually someone we’ve seen before. More specifically, that he was actually an older Billy Maximoff, one of the Scarlet Witch’s sons, also known as Wiccan. To the delight of the viewers, this was exactly the case. Billy possessed the body of William Kaplan, and from there the hijinks began. The inclusion of Wiccan wasn’t just an exciting revelation, but also another potential obstacle for Agatha. But hey, life’s a witch, ain’t it?

“Loki” (2021-23)
What? You mean to tell me that the organization that systematically wipes out anybody who poses a threat to the so-called purity of the timeline isn’t entirely benevolent? Shocking! Pretty early on, viewers suspected that something was seriously wrong with the TVA. And many further theorized that a Kang was the one calling the shots. This would be confirmed later when Loki and Sylvie discovered that the Time-Keepers were all just a sham created by He Who Remains. The major plot point also revealed that this variant of Kang was purposely puppeteering the destruction of countless realities in order to ensure the survival of his own “sacred” timeline. Yeah, that seems just a tad manipulative[a].

“Doctor Strange in the Multiverse of Madness” (2022)
As we approached the second “Doctor Strange” movie back in 2022, there was a good amount of discourse surrounding the Scarlet Witch’s role in the film. “WandaVision” floated the idea of Wanda being more sinister than we thought. With that in mind, it seemed completely possible that her heel turn would be cemented in “Multiverse of Madness”. Sure enough, she ended up being the main villain! Wanda murdered her way across worlds in a desperate attempt to bring her kids back to life. Predicting that she’d break bad wasn’t inherently far-fetched, but seeing it get proven was still pretty validating. Especially for those who predicted it way back in 2019! Quite the magical foresight!

“Avengers: Endgame” (2019) & “The Falcon & The Winter Soldier” (2021)
Legacies can be a tricky thing. When we learned that Chris Evans would be concluding his time as Captain America, everyone wondered who’d be taking up the shield next. Two prominent theories were that either Bucky Barnes or Sam Wilson would become the new Captain America. Though they’ve both been Cap in the comics, Sam seemed more likely. For perspective, Bucky was only Cap for maybe a year while Sam is still Cap in the comics. “Endgame” sowed the seeds for Sam stepping up when an elderly Steve Rogers gifted him the shield. Though he was reluctant to accept it, he’d finally become Captain America at the end of “The Falcon & The Winter Soldier.” Now that’s one serious promotion!

“Avengers: Endgame” (2019)
Thanos’ decimation of half of all life had serious ramifications for all of the MCU, and that included Hawkeye. When the Avenger was notably absent during “Infinity War”, fans assumed he’d come back in a big way for “Endgame”. A popular theory was that he would ditch his Hawkeye costume for one of his other aliases: the Ronin. Another part of the theory suggested that it’d be because of his family getting wiped out during the Blip. This came true in “Endgame” and we were treated to a more vicious Clint Barton than before. It’s just a shame we never saw the true extent of Ronin’s brutality apart from a few scenes in “Endgame” and the “Hawkeye” show. Oh well.

“Captain America: The Winter Soldier” (2014)
As Captain America and Black Widow interrogate Jasper Sitwell in order to find out more about a mass surveillance program called Project Insight, some seriously startling revelations are made. The secret Hydra informant lets it slip that the project is a way to keep tabs on any individuals that might pose a threat to the evil organization. Among the many people of interest are Steve Rogers himself, Bruce Banner, and Stephen Strange. That last name drop in particular got everyone excited. Fans naturally theorized that Doctor Strange would soon enter the fold. The MCU having Doctor Strange sounds like a no-brainer, but since his movie and casting hadn’t been announced yet, the possibilities for where he could show up were endless.

“Thor Ragnarok” (2017) & “Avengers: Infinity War” (2018)
Eagle-eyed viewers always knew that Loki is called the trickster god for good reason. When he noticed the Tesseract being back in Asgard during “Ragnarok,” he took it for himself. From there, viewers assumed that Loki would try to use it in a big way, and he did in “Infinity War”. The villain-turned-antihero used the cube to try and distract Thanos long enough for the Hulk to attack. It didn’t really do much to stop the Mad Titan sadly. In fact, Loki actually died after this, but his actions did confirm that, even in his last moments, he always had a trick up his sleeve.

Various
For the longest time we didn’t know if Marvel’s slew of Netflix shows were canon to the MCU or not. Sure, Kingpin showed up in the “Hawkeye” show and Daredevil was a lawyer in “Spider-Man: No Way Home”. But even when actors from the Netflix shows reprised their roles in official MCU projects, that wasn’t enough. Because maybe, they weren’t actually the same versions… maybe they were just canonically-adjacent variants. See how confusing this gets? It’s got us breaking out the big vocabulary words! Still, many believed the shows were connected, and eventually those fans were proven right. Marvel’s head of streaming Brad Winderbaum ended the debate in 2024 and confirmed they were canon. Great! So how long until Daredevil’s in the next “Avengers” movie?

“Avengers: Endgame” (2019)
Unfortunately, someone was bound to die in this movie. One Avenger that many thought would bite the bullet happened to be Iron Man. Even one of Iron Man’s own comic book writers, Bob Layton, believed it would happen. In a way, it made total sense - someone needed to complete the ultimate sacrifice to stop Thanos. So, who better than the Avenger that started off the entire MCU? Plus, Robert Downey Jr’s contractual status with Marvel Studios at that time suggested he was winding down. Suddenly “Endgame” seemed like the perfect place to have Tony Stark’s swan song. While Tony did die in “Endgame,” proving this theory right was a bittersweet victory in the end. Sure, the fan theorists won, but at what cost?

“Spider-Man: No Way Home” (2021)
The third MCU Spider-Man film had to have been one of the most eagerly anticipated MCU projects ever. Seriously, you just had to be there! One of the biggest reasons for the hype was because of the theory that Andrew Garfield and Tobey Maguire would return as Spider-Man. This also led to other theories that came true, like Andrew’s Spidey being the one to save MJ. The idea of Tobey and Andrew coming back was the talk of the town for months. So getting to actually see our wildest dreams be proven true was a moment like nothing else. We got to see three different Spider-Men saving the day: what’s cooler than that? This was a multiverse movie done right!

“Captain America: The First Avenger” (2011)
At the end of “The First Avenger,” it seemed like Johann Schmidt got what was coming to him when the Tesseract disintegrated him. However, fans weren’t convinced they’d seen the last of the Red Skull. When the Tesseract (AKA the Space Stone) was shown to be able to teleport people and open portals, that was all the evidence they needed. Fans knew he’d pop up again somewhere, only having been teleported. But no one could’ve guessed he’d been transported to the planet Vormir to become the guardian of another Infinity Stone. Even though Hugo Weaving didn’t return for the role, it was a nice surprise to see the villain appear in “Infinity War.”

“Moon Knight” (2022)
The MCU has made several changes when it comes to character history. In “Moon Knight,” we saw Steven Grant discover he was an alternate personality to superhero Marc Spector. While casual viewers enjoyed watching the dynamic between two Oscar Isaacs, comic readers knew the character was one personality short. When the show began airing, it seemed like Marvel was only going to include the two…until hints towards the third started rolling in. It became a game to theorize which moments Jake could’ve had control over. Episode 4’s asylum twist offered the biggest clue; a second sarcophagus made it all but clear there was a third personality. Jake Lockley’s existence was finally confirmed in the finale’s mid-credits scene.

“Avengers: Infinity War” (2018)
Iron Man’s Hulkbuster armor made its glorious debut in “Age of Ultron” where Tony used it to subdue a mind-altered Hulk. Among the many hype-inducing shots from “Infinity War’s” first trailer, fans were delighted to see the armor make a return. Then began the theorizing. It didn’t seem likely Tony would need it for the Hulk again considering Bruce’s arc in “Thor: Ragnarok.” While several characters were guessed to be the operator, most evidence pointed towards Hulk himself. This included an earlier shot in the trailer showing Bruce next to one of the suit’s arms. When “Infinity War” released, the theory was proven true. Although, he only needed it because his alter ego refused to come out.

“Thor: Ragnarok” (2017)
When Thor debuted in the MCU, he craved the chance to one day be King of Asgard. But some hard-learned lessons made him realize he didn’t want it. As “Ragnarok” approached, some fans theorized that he’d be forced onto the throne with the passing of his father, Odin. Ragnarok is an important event in Norse myth detailing the destruction of Asgard and the death of Odin, among many other deities. Plus, with the Goddess of Death, Hela, as the villain, it seemed like a safe bet. In the movie, Odin does die, albeit peacefully, leaving Thor to be crowned as King by the end. However, he’d soon give up the crown to Valkyrie, who’d rule over New Asgard.

“Iron Man 2” (2010)
One of the most widespread MCU fan theories stated that Peter Parker had been in the MCU far longer than we were told. During the climax of “Iron Man 2,” Tony swoops down to save a kid from a Hammer Drone. Though he’s wearing a mask, the theory that this boy is actually Peter got a lot of love from fans. It made sense, too; the Stark Expo was held in Queens, Peter’s hometown, and the boy’s age matched how old Peter would’ve been around that time. While promoting “Spider-Man: Homecoming,” Tom Holland confirmed that the theory was indeed true, even citing producer Kevin Feige. It was nice to have an earlier connection between the two heroes, even a small one.

“Avengers: Age of Ultron” (2015) & “Thor: Ragnarok” (2017)
At the end of “Age of Ultron,” Hulk flew off in a Quinjet, leaving his teammates behind. His exit caused many to speculate where we might see him next. Despite actively not showing him leave Earth’s atmosphere, many fans hoped for a “Planet Hulk” adaptation. With Universal still owning the distribution rights to solo Hulk films, some guessed we’d see him in “Thor: Ragnarok” after he was confirmed to not appear in “Civil War.” Though Marvel couldn’t do the exact storyline, elements from the popular comic run did appear in “Ragnarok.” These include the planet Sakaar and Hulk as a gladiator, though most of his storyline was completely different.

“Captain America: Civil War” (2016)
When “The Amazing Spider-Man 2” failed to meet Sony’s expectations, the studio struck a deal with Marvel to bring the hero into the MCU. Being one of Marvel’s most cherished characters, fans immediately began theorizing about which movie he’d make his debut in. The popular consensus was “Captain America: Civil War.” However, some even theorized about this before Sony and Marvel’s deal simply based on how big of a role he played in the original comic. Although “Civil War” released less than a year after Tom Holland’s official casting, that’s exactly where he debuted. It’s unfortunate that another film’s poor reception helped this happen, but we were ecstatic to see him.

Various
The legendary Stan Lee began making cameos in Marvel movies long before the MCU, but fans were happy to see him keep with the tradition. His constant appearances birthed the popular theory that he wasn’t just making cameos, but playing the same character across all movies. More notably, fans believed him to be Uatu, member of a race called Watchers that witnessed but didn’t interfere with events across the multiverse. This theory ended up coming true…sort of. “Guardians of the Galaxy Vol. 2” showed that while he wasn’t Uatu, he was the same character and he did inform the Watchers about events within the MCU. The actual Uatu wouldn’t appear until the Disney+ series, “What If…?”

“Avengers: Age of Ultron” (2015) & “Avengers: Endgame” (2019)
While Mjolnir will always be connected to Thor, there are a handful of other characters that have wielded the mighty weapon in the comics. Some fans may have wondered if we’d ever see such an occurrence in the MCU, and they got their first tease in “Age of Ultron.” While celebrating a victory, the Avengers tested if any of them could pick it up. Cap producing a small budge led many to believe he’d one day wield it. Though Vision ended up lifting it later, that tease made it clear to many that it was only a matter of time before Steve showed his worthiness. In one of the franchise’s most cheer-worthy moments, Cap made all our wishes come true in “Endgame.”

“Ant-Man and the Wasp” (2018) & “Avengers: Endgame” (2019)
First introduced in “Ant-Man,” the Quantum Realm played a much bigger role than many may have initially guessed. When Scott Lang entered the extremely small universe, many fans correctly guessed this would lead to the eventual rescue of Janet van Dyne. That came to be in its sequel, “Ant-Man and the Wasp.” But the theorizing about the importance of the Quantum Realm didn’t stop there. Following her rescue, Janet made mention of the Quantum Realm’s time capabilities. So when Thanos snapped out half of existence, fans then guessed that the Quantum Realm would be used for time travel to undo his actions. When “Endgame” released, those fans were proven right.

Is there another MCU fan-theory that turned out to be true that we forgot? Break it down in the comments!




[a]apparently the U.S. pronunciation of "manipulative" is not what I thought https://dictionary.cambridge.org/dictionary/english/manipulative