Tony Stark’s friendship with Peggy Carter adds depth to his rivalry with Steve Rogers, as he knew the woman Rogers had to leave behind.
The theory that Tony Stark’s arc mirrors Black Sabbath’s song “Iron Man” suggests his experiences in the MCU align with the song’s lyrics.
The theory that Howard Stark injected Tony with a variation of the Super Soldier Serum explains his remarkable intellect and survival abilities.

As Iron Man is one of the most popular characters in the MCU, and as such, many fan theories have sprung up that completely transform the hero’s story in the franchise. First appearing in 2008’s Iron Man, Tony Stark’s role in the Marvel Cinematic Universe was one of leadership and innovation, both narratively and figuratively. As well as leading the Avengers on-screen, the characterization of Iron Man paved the way for the MCU’s massive success: he was written to be far more complex than many superhero movies had attempted before. This mingling of humor and heroism created the framework for the MCU’s future, also prompting the creation of multiple Iron Man movies.

Given the character’s pivotal role in the franchise, many theories have emerged that subtly alter his MCU story. The most compelling among these use evidence from all along the MCU’s movie timeline to explain and reframe elements of Tony Stark’s arc, thereby transforming the franchise’s Iron Man movies. Though the majority of these theories are impossible to confirm and rely heavily on speculation, they are especially impressive for their creativity, attention to detail, and ability to create a fresh perspective on the MCU’s Iron Man stories. Here are 10 fan theories that completely change how you watch Iron Man movies.

Related: All 10 Characters Carrying On Iron Man’s MCU Legacy After His Death

10 Tony Stark Was Close Friends With Peggy Carter

The MCU’s Peggy Carter is most closely connected to Steve Rogers, but there’s a theory that Tony Stark also knew her quite well. As seen in Captain America: The First Avenger, Howard Stark and Peggy Carter were close friends, and later went on to found SHIELD together. Considering the connection between Tony Stark’s father and Carter, it seems likely that the hero knew her in his pre-Iron Man days. This adds an extra layer to the friendship and rivalry of Stark and Rogers, as Stark was able to grow up knowing the woman that Rogers had been forced to leave behind.

9 The Identity Of A Reporter At Tony Stark’s Iron Man Press Conference

At one of the earliest junctures in Iron Man’s MCU timeline, a throwaway line actually led to an optimistic but interesting theory. During Stark’s press conference at the end of Iron Man, he addresses a reporter as “Ben”. Theories that this could either be Ben Urich or even Ben Parker seek to connect the moment to other Marvel Comics characters, linking Iron Man to other Marvel heroes in the process. Though it wouldn’t be the most groundbreaking revelation, the theory posits that Iron Man was once intended to link more directly to either Daredevil or Spider-Man early in the MCU.

8 Tony Stark’s Arc Mirrors Black Sabbath’s “Iron Man”

Though the song and the character are unconnected, there’s a theory that the use of Black Sabbath’s “Iron Man” during the credits of the first MCU movie was an intentional tease of his arc. The song’s lyrics follow a man who travels through time to witness the end of the world and is changed by his experience. Much of the imagery used in the lyrics meshes with Stark’s travel through the wormhole in The Avengers and his visions of the apocalypse in Age of Ultron leading to his creation of a potentially apocalyptic threat.

7 Iron Man’s MCU Story Was Molded By His Endgame Time Travel

In the final chapter of Iron Man’s MCU story, he travels back in time and meets his own father. There’s a theory that this is actually what sends him on the path to heroism: his father supposedly recognizes his son as the man who once visited him, then begins to subtly teach and condition young Tony to become the great hero he grows up to be. The theory may be somewhat far-fetched, but it’s a touching and self-contained way of explaining how Stark shaped his own destiny and made himself one of the world’s greatest heroes.

Captain America: The First Avenger sees Howard Stark meet Steve Rogers and help create Captain America, and there’s one theory that claims this event shaped Iron Man’s own story. After meeting Rogers, Howard supposedly imparted the same sense of patriotism and duty onto his son (via their weapons manufacturing business). Having grown up hearing stories of Cap’s incredible virtues, Stark is later heartbroken by Rogers’ insistence that Stark isn’t a hero. This then leads to Iron Man’s final act of sacrifice, making his whole story one in which he lives up to Cap’s example and reframing his whole narrative arc.

5 Howard Stark Injected Tony With Super Solider Serum

Howard Stark is introduced as the man who helped create the Super Soldier Serum which turned Steve Rogers into Captain America. There’s a theory that he later injected his son with a variation of the serum, gifting him with remarkable intellect and longevity. As Tony Stark is depicted as the most intelligent and creative person in the MCU and regularly survives ordeals that would kill any ordinary human, the theory carries a remarkable amount of weight. The theory suggests that if the serum does indeed enhance the natural attributes of its host, then Stark’s scientific mind was supercharged by his father’s attempts to recreate Erskine’s serum.

4 Jarvis Is The Real Hero

One of the most simple theories surrounding the Iron Man movies is also the most compelling: that Jarvis is the real brains behind the hero. Throughout his solo trilogy, Tony Stark is shown asking Jarvis for help with various complex tasks, with the AI program helping to design and pilot his armor as well as operate many of its more delicate systems. The theory simply suggests that Jarvis does the majority of the work, allowing Stark to act as the hero while minimizing the danger to his creator through countless actions, supporting Stark’s operation of his powerful armor in practically every way.

3 Stark’s Sacrifice Was Because Of His Oldest Broken Promise

Of all of Iron Man’s sins in the MCU, Stark himself considers his worst mistake the creation of countless weapons. Despite promising in Iron Man to stop making weapons, Stark’s creations are repeatedly used to cause death and destruction, and there’s a theory that his eventual sacrifice was intended to right this wrong. Throughout the MCU, Stark’s technology has been used for evil, whether by Obadiah Stane, Ivan Vanko, Justin Hammer, or Ultron. According to the theory, after inventing time travel, Stark realizes the reality-ending potential of the technology and sacrifices his life to protect its secrets and his original promise of peace.

2 Thanos Is Terrified Of Tony Stark Because Of The Avengers

In Avengers: Infinity War, it’s revealed that Tony Stark is the only Avenger that Thanos actually admits to knowing. One theory suggests that this is because of Iron Man’s actions in The Avengers, when he single-handedly flies a nuclear missile through a wormhole to destroy the invading Chitauri fleet. From Thanos’ perspective, Stark is a single man who faced and decimated an entire army in mere seconds, with the theory positing that this display of fearless and raw power was able to scare even Thanos into remembering Iron Man over his fellow Avengers.

1 Stark’s Arc Reactor Is Derived From An Infinity Stone

Iron Man 2 sees Tony Stark use one of his father’s discoveries to create a new element to power his arc reactor. One surprisingly coherent theory claims that the element is derived from the Tesseract after Avengers: Endgame showed Stark working with the Infinity Stone. Howard explains that technological limitations prevent him from creating the element, and Jarvis confirms that it’s not a known compound on Earth. This seemingly confirms that the element is related to the Space Stone, and is even suggested to explain how Stark was able to wield the Infinity Gauntlet in Iron Man‘s heroic final moments.

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 These theories have big implications for Iron Man.  Read More