New Avengers: Infinity War Fan Theory Explains Captain Marvel's Whereabouts

When describing the Marvel Cinematic Universe, one would be inclined to use words like "sprawling," "expansive," and "exhilarating." It's got action for days and surprise twists to keep fans hanging on for months in between installments. It's got over a decade's worth of stories that make viewers laugh, cry, and drop their jaws in amazement. And, of course, it's filled with a multitude of heroes from different walks of life, all with different abilities and (often tragic) backstories. 

One hero who's been missing until very recently, though, is Captain Marvel, also known as Carol Danvers. An intriguing new fan theory, unearthed and brought into the spotlight by the sharp-eyed folks at We Got This Covered, seeks to explain why that is. 

The U.S. Air Force officer-turned-superhero has been in the Marvel Comics world for more than 50 years — since her debut in Marvel Super-Heroes #13 in March of 1968 – but she hadn't so much as made a cameo appearance in the MCU until her name was included in the post-credits scene in Avengers: Infinity War when Nick Fury (Samuel L. Jackson) sent her a message asking for her help. 

Without explicitly addressing it, that moment essentially confirmed that Captain Marvel has been hiding in the background of the MCU and possibly interacting with Nick Fury off screen. But where has she been for the last 10 years of MCU magic? And why did Nick wait until the prune-faced Titan Thanos (Josh Brolin) killed half the universe's population to request her assistance?

Posted to Reddit by user meme_abstinent, the new theory posits that Captain Marvel, who will make her official debut in the 1990s-set, Brie Larson-led solo film in March of 2019, has been missing from the MCU since the '90s because she's been "time traveling through the Quantum Realm."

"What's she doing hopping through time?" one might ask. 

Well, the theorist speculates that the end of Captain Marvel will see humankind narrowly evading "intergalactic war" with extraterrestrial shapeshifters known as the Skrulls and Nick directly witnessing the power the villainous aliens possess. The assumption is that, in the final moments of the film, Captain Marvel learns that the Skrulls' domination has actually spread beyond the United States — and beyond Earth as well. 

"Now, turns out the Skrulls have indeed infiltrated multiple levels of Earth's infrastructure and the world's most powerful governments. Not just Earth but many other planets," the theory reads.

Hoping to save the universe and clear out the war-obsessed creatures, Captain Marvel time travels through the Quantum Realm "to begin eliminating the impostors." So says the theory, at least. 

"So, what does this all have to do with Nick communicating with Captain Marvel in Infinity War?" the same inquisitive person may question. 

According to the theory, Captain Marvel journeying through the Quantum Realm explains why she's in the past but Nick can still get in contact with her. And the Skrull invasion that sparked her time travel? That links to the reason why Nick held out on calling her for so long: "he thought that the Snappening in Infinity War was Skrull related."

"Clearly if she was an inactive hero or lost in space he wouldn't have a pager on him at all times," the theorist writes. "He made that pager to call her if the Skrulls were invading again because by the end of her movie he knows she has a universe to protect, not just an Earth."

Collating what we already know about Captain Marvel and the Quantum Realm, we have a pretty good feeling about this theory's plausibility. 

Nick Fury is confirmed to appear in the film, albeit without his signature eye-patch, and it's long been teased that Captain Marvel will involve the Quantum Realm in some way or another. 

In 2017, Ant-Man consultant and quantum physicist Dr. Spiros Michalakis hinted that the realm will help shed light on Carol Danvers' story and how she fits into the MCU. Speaking about quantum theories and their inclusion in the MCU, Michalakis told Inverse, "This is exciting for the future. There are different ways that some of these ideas appear on screen in a few years. Not just for Ant-Man, but also for Captain Marvel and all of the Marvel Cinematic Universe."

Marvel president Kevin Feige also previously teased how the Quantum Realm could be used past Ant-Man and the Wasp, which debuted in July of 2018. "There are things that you see back there that [Ant-Man and the Wasp director] Peyton [Reed] has put in there," Feige told ComicBook.com. "Where and how they pay off in the near term and the long term remains to be seen."

In all, this theory sounds like a perfectly reasonable explanation as to where Captain Marvel has been all this time. But with Marvel being the secretive studio it is, fans likely won't get any official follow-up on these ideas until Captain Marvel is released on March 8, 2019.