Now that Robert Downey Jr. is returning to the MCU, Marvel Studios has the perfect opportunity to address an annoying 12-year-old mystery that started back in Iron Man 3 and was made more curious in Avengers: Endgame. There are countless unanswered questions and loose ends in the MCU that Marvel Studios is yet to address, and some of these have gone unresolved for many years. The fact that several past MCU actors will be returning for Phase 6’s Avengers: Doomsday and Secret Wars, however, creates the opportunity for some of these mysteries to be solved.

Perhaps most notably, Robert Downey Jr. will be returning in Avengers: Doomsday, though he’ll be playing the villainous Doctor Doom instead of his former MCU hero, Tony Stark’s Iron Man. While the details concerning this recast haven’t yet been revealed, it’s possible that Downey Jr.’s return could provide the chance for some of Iron Man’s unresolved storylines to finally receive closure. This includes one thread from 2013’s Iron Man 3 that got a new burst of attention after a surprise appearance in Avengers: Endgame but hasn’t been touched since.

Iron Man 3 & Avengers: Endgame’s Harley Keener Has Never Been Properly Explained In The MCU

Ty Simpkins Debuted As Harley Keener In Iron Man 3

At 11-years-old, Ty Simpkins made his MCU debut as Harley Keener, a young kid from rural Tennessee who helps Tony Stark investigate Aldrich Killian’s Extremis bombings. Keener had a fairly large role in Iron Man 3, too large to be just a supporting character in one MCU movie, which led many to speculate about Ty Simpkins’ possible return to the role. This didn’t happen until Avengers: Endgame, which saw Harley Keener appear among Earth’s Mightiest Heroes paying respects to Tony Stark at his memorial service.

Now that Ty Simpkins is 23-years-old, the time may be right for him to finally return to the MCU. This could provide some explanation about his significance in Iron Man 3, how he knew to return in Avengers: Endgame, and what he has been up to in the time between these two Infinity Saga movies. Harley Keener could become one of the most important characters in the MCU, and, given his connection to Tony Stark, Robert Downey Jr.’s return to Marvel might make Keener’s return all the more likely, too.

Robert Downey Jr.’s Recast Would Make Ty Simpkins’ MCU Return More Powerful

Harley Keener Could Come Face-To-Face With RDJ’s Doctor Doom

While it would have originally been great to see Harley Keener reunite with Tony Stark, who became his friend and mentor in Iron Man 3, this reunion now has a dark twist after Robert Downey Jr.’s recast as Doctor Doom. The iconic Marvel villain will have the same face as Tony Stark, which will surely confuse and anger several MCU heroes when they come face-to-face with Doctor Doom in Doomsday and Secret Wars. The likes of War Machine, Spider-Man, Doctor Strange and Bruce Banner will likely be affected by Downey Jr.’s villainous debut, and Harley Keener could join them.

While Harley Keener’s story in the MCU has been a mystery since 2013’s Iron Man 3, his return and twisted introduction to a supervillain who shares a face with his trusted mentor could provide him with the motivation to become a hero in his own right. Ty Simpkins’ character played a huge role in Stark’s recovery in Iron Man 3, and was important enough to appear at Stark’s funeral, so it would be hugely poignant to see Harley Keener battle Downey Jr.’s Doctor Doom in Phase 6. This could support a wild MCU superhero theory.

Harley Keener Could Finally Become A Theorized MCU Hero In Avengers 5 & 6

Harley Keener Could Replace 1 Kang The Conqueror Variant In The MCU

Ever since he first appeared in the MCU back in 2013, there has been speculation that Harley Keener may be destined to become an Iron Man-esque superhero in the MCU. Keener’s connection to Tony Stark, clear genius-level intellect and affinity for technology and gadgets hinted at a heroic evolution for him, but this hasn’t yet come to pᴀss. One of the most popular theories suggested that Harley Keener could become the MCU’s version of Iron Lad, who is a young, heroic variant of Kang the Conqueror in Marvel Comics, and, now, it seems this could be possible.

Jonathan Majors portrayed several variants of Kang, including the Conqueror himself, in Loki and Ant-Man and the Wasp: Quantumania before being fired from Marvel Studios after his 2023 arrest and conviction. Kang’s future in the MCU is uncertain now, especially after Avengers: The Kang Dynasty has been changed to focus on Doctor Doom as Doomsday. To further remove Kang, Marvel Studios might completely alter Iron Lad in the MCU, which could see Harley Keener return as the armored hero, entirely separate from Kang, but intricately connected to Tony Stark’s legacy as Iron Man.

Harley Keener’s Iron Lad Would Be Important For 1 Upcoming MCU Avengers Team

Marvel Studios Has Been Teasing The Young Avengers

This young variant of Kang the Conqueror was created in Marvel Comics when the older iteration took him from his timeline before his villain-making event. While Kang wanted to train the young Nathaniel Richards to be a better villain, Nate actually saw the error of his older variant’s ways, and traveled to the past in hopes of avoiding his destiny. He sought the Avengers’ help, but found them disbanded, which led to him downloading the Vision’s operating system and discovering plans for the Young Avengers team, the new generation of heroes, which he subsequently formed.

Eventually, Nate Richards realizes he must fulfill his destiny to ultimately protect his friends, forgetting his time as a Young Avenger. Since he is pivotal in bringing the team together, however, it would be a shame to build the MCU’s Young Avengers team without Iron Lad. If Iron Lad is not going to be a variant of Kang the Conqueror in the MCU, and may instead be a hero following in Iron Man’s footsteps, akin to Ironheart, Ty Simpkins’ Harley Keener would be perfect to ᴀssume the role and become a Young Avenger.

Marvel Studios has already hinted at the formation of the Young Avengers several times, most notably at the end of 2023’s The Marvels, which saw Kamala Khan and Kate Bishop begin to plan forming a new team of young heroes. Other possible members could include Cᴀssie Lang, the newly-reincarnated Billy and Tommy Maximoff, America Chavez, Riri Williams and more. Should he return, Harley Keener would be an incredible addition to the team, especially if he becomes Iron Lad and joins the fight against Doctor Doom, perfectly paying off his Iron Man 3 debut.

Upcoming MCU Movies

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  Captain America: Brave New World

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  February 14, 2025
  

  
  
  
  

  
  

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  Thunderbolts*

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  May 2, 2025
  

  
  
  
  

  
  

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  The Fantastic Four: First Steps

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  July 25, 2025
  

  
  
  
  

  
  

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  Avengers: Doomsday (2026)

  
  
  
  
  

  
  

  
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  Spider-Man Homecoming 4

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  July 24, 2026
  

  
  
  
  

  
  

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  Avengers: Secret Wars

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  May 7, 2027
  

  
  
  
  

  
  

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