At this year's San Diego Comic-Con, Marvel Studios made headlines with a number of significant reveals about the future of the Marvel Cinematic Universe. Among the most exciting things we learned is that 2019's Captain Marvel will pit Brie Larson's title character and her allies against the nefarious alien race, the Skrulls. First introduced in 1961's Fantastic Four #2, the Skrulls recently (well, 9 years ago) wreaked havoc throughout the Marvel Universe in 2008's crossover event, Secret Invasion. During that arc, they used their shapeshifting and power-mimicking abilities to strategically abduct and take the place of several prominent Marvel characters in an attempt to destabilize the various defenses of Earth until it was ripe for the taking.

With the Skrulls' impending cinematic debut, it wouldn't be surprising if the MCU started to lay the groundwork for a big-screen Secret Invasion, revealing that not every hero (or villain) we've come to know and love is who they seem. Read on for the 15 MCU characters who could really be Skrulls in disguise!

Captain Marvel

Brie Larson Captain Marvel Fan Art

Carol Danvers is one of the most formidable heroes in the Marvel Universe, thanks to her altered genetic code that makes her practically half-Kree (the same species as Ronan, the villain in Guardians of the Galaxy). She is capable of flight, has super-strength comparable to Thor and Hulk, and can absorb massive amounts of energy and redirect it through concussive photonic blasts from her hands. That kind of power seems like it would have been quite useful against the Chitauri and Ultron...

Now that Marvel has announced that Nick Fury will be fighting alongside Carol in her solo movie, which takes place in the 1990s, one has to wonder why he didn't call on her when he first started the Avengers Initiative, and where she's been for the last 20-odd years. Does she in fact make it through the events of her film unscathed, or has she been a prisoner of the Skrulls this whole time? It could be that the Carol the team is sure to meet in Avengers 4 is not the real Captain Marvel at all.

Tony Stark

Captain America: Civil War - Robert Downey Jr. as Tony Stark

This one could be a longshot (what are the odds Robert Downey, Jr. consents to playing a villain after all this time?), but there is a case to be made that some of Tony Stark's actions since he joined The Avengers have been, at best, reckless, and at worst, patently destructive.

His creation of Ultron, which at the time he claimed was to ensure that the world had protection if The Avengers could no longer provide it, nearly brought about the end of the human race. But what if that was an intended feature rather than a bug? What if Tony was abducted at some point during or after The Avengers and his imposter has been planting seeds of discord ever since? Again, as Tony has been the backbone of the MCU since its inception, it would be a pretty unlikely turn of events to have him exposed as an enemy, but the possibility of the narrative gut-punch of such a reveal is too much to ignore.

Hank Pym

Michael Douglas as Hank Pym in his lab

The former Ant-Man should be considered on any list of possible Skrull impostors if for no other reason than that he was abducted and replaced in the comic book storyline. While it's true that the big-screen version of Hank Pym has played a far less prominent role in the Marvel Universe thus far than the Pym we know from the comics, that doesn't mean he won't meet the same fate in any Secret Invasion adaptation.

Like in the comics, the MCU's Pym has a long history of scientific contributions between his time with S.H.I.E.L.D. and his company, Pym Technologies. A man with those resources is a valuable asset for a force with aims on invasion. Though his expulsion as CEO of the company he started would certainly prove to be an obstacle, he (or something posing as him) could be on the way to regaining his standing through his work with Ant-Man and Wasp.

Black Widow

Scarlett Johansson as Black Widow from Avengers: Age of Ultron

During the events of Secret Invasion, we discover that Spider-Woman, a trusted member of the Avengers and S.H.I.E.L.D., has in fact been replaced at some point in the past by the Skrull queen, and that she's been working against the heroes for a year or more. It's a shocking reveal, and while Jessica Drew has not yet been introduced in the MCU, the filmmakers could elect to have her role in the story filled by Natasha Romanov instead.

Black Widow has been a stalwart of the Avengers since the start, and she has commonly been the voice of reason when other Avengers begin to lose their way. For our heroes to learn that she has been replaced by a creature determined to put more "red in the ledger" would be a truly devastating moment.

Pepper Potts

Pepper Potts sitting at her desk in Iron Man 2

Tony Stark and Pepper Potts have a long and complicated relationship. Pepper was the first one to learn of Tony's extracurricular activities, and despite her better judgment much of the time, she has supported and protected him throughout his tenure as Iron Man.

But things have not always been smooth sailing for the couple. Pepper nearly perished at the hands of Aldrich Killian and his Extremis virus in Iron Man 3, which may have contributed to the falling out Tony mentions to Steve Rogers in Captain America: Civil War. Strange it seems, then, that the next time Pepper appears on screen, at the end of Spider-Man: Homecoming, she and Tony are at a high point in their relationship, with even talk of an engagement being bandied about.

Now, it very well could be that Pepper reconciled with Tony completely of her own accord (it's been known to happen!). But perhaps the Skrulls realized that Tony's affection for Pepper could be used against him, and they have positioned one of their own to be by his side, ready to backstab him or steer him towards their nefarious goals at a moment's notice.

Thaddeus "Thunderbolt" Ross

Thaddeus Ross meets with the Avengers in Captain America: Civil War

Before Captain America: Civil War, the last time we had seen General Thunderbolt Ross, he was a defeated man, having made an Abomination-sized mistake in his obsessive quest to take down Bruce Banner and his green-skinned alter ego. It's quite the turnaround indeed to go from the architect of the destruction of Harlem to U.S. Secretary of State.

It makes one wonder what exactly the general did to mend his certainly damaged standing to the point that he'd be entrusted with a cabinet position. Did he in fact take his monstrous failure in The Incredible Hulk and use it as motivation to climb the government ladder? Or was he preyed upon at his lowest moment by an opportunistic species and replaced by a more expertly manipulative creature than him? There's got to be more behind the turnaround than that throwaway golf story he mentioned in Civil War.

Phil Coulson

Agents of SHIELD Season 3 Clip Coulson Hard Choice

Phil Coulson was one of the first threads to start tying the separate entries in the MCU together. His appearances in Iron Man and Thor introduced the moviegoing world to the Strategic Homeland Intervention, Enforcement, and Logistics Division, and his death in The Avengers proved to be the catalyst that helped the heroes work as a team. As we all know, though, death in comic books is more of an inconvenience than anything else, and so it was for Agent Coulson, as he has been back covertly running S.H.I.E.L.D. for four seasons now.

But how can we know for sure that Coulson ever came back from the dead at all? True, Agents of S.H.I.E.L.D. has provided some details regarding his resurrection, but the possibility of a retcon, that good old-fashioned comic book trope, can never be dismissed. Plus, having Coulson, Director of S.H.I.E.L.D., revealed as a Skrull in the lead-up to Secret Invasion in Phase 4 would be the perfect way to tie Marvel TV back in with the movies.

Sharon Carter

Emily VanCamp Captain America Civil War Sharon Carter Romance

As we learned in Captain America: Civil War, Sharon is the great niece of S.H.I.E.L.D. co-founder and Cap's first love, Peggy Carter. If the Skrulls are worth their salt as intergalactic conquerors, they will have had their eye on Earth for quite a while in preparation - long enough to understand both the threat and the value Peggy and S.H.I.E.L.D. itself pose to their goals.

Infiltrating her family and her organization would guarantee a tactical advantage, as Sharon has access to people and information critical to the defense of Earth. That advantage has grown even stronger now that Steve Rogers has recently developed feelings for Sharon, leaving one of the most powerful and influential heroes on the planet - particularly once he is no longer viewed as a war criminal - vulnerable to manipulation as the Skrull invasion nears.

Maria Hill

Cobie Smulders as Maria Hill in Avengers Age of Ultron

The most dependable ally of Nick Fury (more on him later), former S.H.I.E.L.D. Deputy Director Maria Hill has played a substantial role in monitoring and eliminating threats like the Chitauri invasion. Hill's loyalty to Fury has also extended beyond her time at S.H.I.E.L.D., leading her to work closely with (or perhaps gather intel on) Fury's brainchild, The Avengers. After HYDRA's infiltration caused the downfall of S.H.I.E.L.D., she dedicated herself to working alongside the super-team rather than for the government she used to serve.

With all that said, Hill (along with her mentor) was conspicuously absent from the events of Captain America: Civil War, begging the question of whether she was in fact content to watch the team splinter from a distance as she worked towards a more nefarious endgame.

Heimdall

One thing to remember is that the Skrulls - at least as we know them in the comics - have been around threatening civilizations like the Kree for millennia. The same can be said for our friends the Asgardians, and it is entirely possible that they have confronted a Skrull invasion themselves. What if, upon failing to conquer Asgard at some point in the past, the Skrulls simply elected to use a certain all-seeing, Bifrost-guarding Asgardian as a means to seek out other, more susceptible worlds?

Before the Bifrost Bridge was destroyed during the events of the first Thor, Heimdall had all the time in the world to gather information on the Nine Realms and relay back to his home world that Midgard in particular, with its warring nations and unstable alliances, is a prime candidate for occupation. On a more straightforward note, Heimdall's certainly sporting a different look in Thor: Ragnarok than anything we've seen previously.

One of Thanos' Black Order

What the Avengers: Infinity War Poster Reveals

Other than the fact that they will appear in Avengers: Infinity War, we have no information on the role Thanos' "children" - Corvus Glaive, Proxima Midnight, Ebony Maw, and Cull Obsidian - will play in the Mad Titan's quest for the Infinity Stones. It may be that the four Black Order members will serve primarily as their father's gophers and henchmen, but one confirmed member (if he is anything like his comic book counterpart) is much more dangerous as a talker than a fighter.

Ebony Maw has the ability to persuade people (or even extraterrestrial despots) to do anything he says. If the Skrulls do in fact have designs on Earth and, through observation or machination, have learned that some of the stones Thanos so desires are there, it would make a lot of sense to have one of their own whispering in the purple one's ear, facilitating his destruction of Earth's Mightiest Heroes and allowing the Skrulls to pick up whatever pieces of Earth remain.

Everett Ross

Martin Freeman wearing a suit in Captain America Civil War

We have only just been introduced to CIA operative Everett Ross, but he is clearly a man of import within the MCU's intelligence community. He also seems to be particularly interested in the way superpowered individuals interact with the government. After serving as a high-level liaison with the Avengers during the events of Captain America: Civil War, trailers for next year's Black Panther have shown that Ross becomes involved in the affairs of Wakanda as well.

Ross' actions suggest on the surface that he wants to work alongside the Avengers (so long as they have signed on the dotted line of the Sokovia Accords) and T'Challa to fight global threats. But he also happens to be in a unique position to learn critical details about the weaknesses of the US government and the Avengers, the technological advancements of Wakanda, and other potential obstacles to an invasion.

Happy Hogan

Jon Favreau's Happy Hogan has been loyal to Tony Stark since the very beginning, from welcoming his boss home after his kidnapping in the Middle East to taking the lead on packing up Avengers Tower and babysitting a certain web-slinging teenager.

As Tony's driver, bodyguard, and head of security, Happy has the trust of one of the most powerful people on the planet - exactly the kind of position that would be coveted by an infiltrating alien race. In Iron Man 3, Happy was nearly killed in an explosion as he was investigating Aldrich Killian's Extremis henchman, Eric Savin. From everything we have seen since, he's made a full recovery. But being on death's door in a hospital bed certainly makes one an easy target for an abduction. There's every chance that the Happy that pulled through after his close call is not the same one that Tony Stark trusts with his life.

Hulk

Hulk in his gladiator armor stepping into the arena in Thor Ragnarok

Thor: Ragnarok will finally (presumably) reveal what happened to Bruce Banner after he flew off in the Quinjet at the end of Avengers: Age of Ultron. One thing that is clear even now, months before the movie's release, is that somehow he wound up leaving Earth entirely, eventually becoming a gladiator for Jeff Goldblum's The Grandmaster. But what happened in between? There is every possibility that Hulk encountered other alien races before making his living in the ring - one of those could easily have been the Skrulls.

If they have been paying attention to Earth, the Skrulls would know that the Hulk is quite possibly the most dangerous weapon on the planet, and they would be stupid not to take advantage of an opportunity to take him out of the game entirely as they prepare for their invasion. Granted, it would take some serious foresight to take Hulk's place and position their impostor on a faraway planet so that he is there when Thor is captured, but the fact remains that the Green Goliath's whereabouts the past few years are a complete mystery.

Nick Fury

Screenshot Iron Man 2 Nick Fury

For our money, the most likely candidate to be a secret Skrull is the founder of the Avengers Initiative himself, Colonel Nicholas J. Fury. As was announced at Comic-Con, a two-eyed Fury is set to play a pivotal role in Captain Marvel, which will serve as a prequel of sorts to the MCU that we have been accustomed to for the last 9 years. It turns out that Fury had a run-in with the Skrulls before he ever came across a man in an armored suit or an Asgardian thunder god, and we can be reasonably sure that the encounter leaves him in desperate need of an eye-patch.

Or, it could be that Nick Fury never returned from the Skrull conflict at all. If he was taken prisoner or killed and replaced with a shapeshifter, the ripple effect across the MCU is almost too big to accurately measure. Skrull-Fury could have in turn seeded S.H.I.E.L.D. with other impostors (see numbers 7, 8, 9, and 11). The Avengers Initiative itself could simply be a ploy to have control over Earth's most powerful individuals in order to dismantle them when the time was right.

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Do you think the introduction of the Skrulls is leading up to a Secret Invasion in the MCU? Give us your thoughts on who could be Skrulls in disguise in the comments!

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