It's commonly believed that Marvel Studios is gearing up for a "Secret Invasion" plotline that will shake the MCU to its core - but which of the Avengers could secretly be Skrulls? Next year's Captain Marvel will introduce the Skrulls, a shapeshifting alien race from the comics, to the Marvel Cinematic Universe. A warlike people who have been locked in conflict with the Kree for millennia, the Skrulls are notorious for using their shapeshifting powers to infiltrate other worlds before conquering them and plundering their resources for the war.

Over in the comics, the Skrulls are best known for the 2007 "Secret Invasion" event. Spearheaded by writer Brian Bendis, "Secret Invasion" revealed that the Skrulls had spent years - perhaps even decades - working their way into every area of public life on Earth. The Avengers first learned about the Skrull invasion when the Hand's leader Elektra was killed, and her body shifted back to the form of a Skrull. It didn't take long for the Earth's Mightiest Heroes to discover that they had no way of detecting the Skrull duplicates. The event's strapline was a simple but effective one; "Who do you trust?"

Related: Avengers Theory Suggests Hulk Has Been A Skrull Impostor Since Ragnarok

Adding a race of shapeshifting, warlike aliens into MCU history definitely seems to set up the potential for a "Secret Invasion" plotline. What's more, given that Captain Marvel is set in the '90s, the Skrulls will presumably have decades to build up a presence on Earth. That means anyone could potentially be a Skrull - even a member of the Avengers.

This Page: Why the Big Avengers Can't be Skrulls

Page 2: Which Characters Work as Skrulls?

Why the Big Avengers Can't be Skrulls

Iron Man, Hulk, Cap, Thor, and Black Widow corner Loki with Hawkeye pointing his arrow in The Avengers

Back in 2007, Brian Bendis swiftly spotted a potential issue with his "Secret Invasion" arc. The last few years had seen Earth's heroes make morally dubious decisions, as part of both the "Civil War" and the "World War Hulk" events. Some characters actually seemed badly damaged by their arcs, none more so than Iron Man. Several of the tie-ins to "Civil War" had essentially portrayed Iron Man as an out-and-out fascist, and he'd gone so far as to create a prison in the Negative Zone in which he'd imprisoned old friends and allies. Readers immediately began to suspect Iron Man was actually a Skrull, and that this was a convenient strategy to back out of a poorly-received character arc. In an interview with CBR, Bendis insisted that wasn't the case.

"People who spent good money on "Civil War" and now "World War Hulk" can rest assured — as promised that those events happened unto themselves. There’s no sinister doings that we did not reveal. Whatever the plan afoot is for the Skrull Empire 'Civil War' certainly helped it. They let it happen. They were sort of like, 'Oh you guys want to beat the s**t out of each other? Go ahead.'"

In other words, Bendis insisted that the Skrull invasion wasn't responsible for divisive events like "House of M," Civil War," or "Secret War." Rather, the Skrulls simply took advantage of the chaos in the superhero community in order to push ahead with their own plans. Two key Avengers were revealed to be Skrulls; Spider-Woman and Hank Pym. Both had been well-placed, but were only secondary characters in arcs like "Civil War."

Related: Rumor Patrol: Skrulls Will Appear In Avengers 4

Marvel Studios would face exactly the same issues if they revealed any of the main Avengers were Skrulls. Imagine if Tony Stark had been a Skrull impostor for years; Captain America: Civil War would lose all of its emotional impact, because everything Iron Man did in the film would really have been part of a Machiavellian scheme to tear the Avengers apart. Thor's character arc through Thor: Ragnarok and Avengers: Infinity War would lose all meaning if he turned out to be a Skrull. Even the Hulk couldn't really be a Skrull, given Marvel is working on a three-film character arc for the Jade Giant, one that would be completely ditched if it were revealed Bruce Banner had actually been replaced. And as for Spider-Man, there's simply no way Marvel would damage his character arc by revealing he was actually a Skrull.

So the first thing we can say for certain is that the central Avengers simply cannot be Skrulls. That would damage the narrative fabric of the MCU, twisting the stories of previous films to the point where they lost all emotional impact.

Page 2: Which Characters Work as Skrulls?

Scarlet Johansson as Black Widow

Which Characters Work as Skrulls?

Of course, not every Avengers is a franchise lead. We can rule out the likes of Captain America, Iron Man, Thor, Spider-Man, and even the Hulk; but that doesn't mean some of the secondary Avengers couldn't be Skrull impostors instead. Let's take a look at the other members of the Avengers.

It's safe to say that Hawkeye isn't a Skrull impostor. The whole purpose of the Skrull invasion is to infiltrate the Avengers, and Hawkeye's entire character arc is focused around the idea that he actually wants to retire. In the aftermath of Captain America: Civil War, he's spent the last two years under house arrest, and the Avengers didn't even call him in for the Battle of Wakanda in Avengers: Infinity War. Hawkeye is literally the last person the Skrulls would want to replace.

Related: How Marvel Should Handle A Hawkeye Solo Movie

A more promising target would be Black Widow, although again her character arcs from The Avengers through to Avengers: Age of Ultron are a little too pronounced for her to have been a Skrull impostor that far back. But she's ideally positioned to become a huge asset to the Skrulls; a close friend of Steve Rogers, and someone who has a romantic history with the Hulk. What's more, Black Widow's every secret is probably available to the aliens; when she uploaded the S.H.I.E.L.D. database onto the Internet in Captain America: The Winter Soldier, Black Widow told the world everything S.H.I.E.L.D. knew about her. This super-spy's life story is public knowledge. It's true that Marvel is working on a Black Widow movie, but that doesn't rule this idea out. In the comics, the "Secret Invasion" arc saw one Avenger return from the dead, Mockingbird, and she then had to spend time acclimatizing to a world that was very different to the one she knew. In the same way, it's possible the Black Widow script will be centered around Black Widow's return to Earth, and her attempt to rebuild her life.

Scarlet Witch can probably be ruled out as a Skrull. Although the aliens can mimic powers, it's doubtful they'd be able to duplicate the resonant frequency of an Infinity Stone, so the fact she could destroy the Mind Stone rules her out. Meanwhile, the fact that Vision had the Mind Stone in his forehead - and didn't turn back into a Skrull when Thanos removed it - proves he isn't a doppelganger.

That only leaves two other possibilities; Falcon and Winter Soldier. There's no reason the Skrulls would duplicate Bucky, given he's one of the world's most wanted and is hardly free to move with impunity. What's more, like Hawkeye, Bucky has exerted far too much effort into keeping his head down. Falcon, on the other hand, is a definite possible candidate. In narrative terms, he doesn't really have a story of his own; Sam has basically been relegated to the role of sidekick. That leaves him close enough to Steve Rogers for the revelation to be a shocking and emotional one.

Moving to Wakanda, it's unlikely the fictional African nation has actually been infiltrated by Skrulls at all. Until recently, Wakanda was believed to be a backwards country that kept itself to itself. That seems to have only just begun to change, and the Skrulls - like the rest of the world - will no doubt be taken by surprise when they realize just how advanced the Wakandans really are. The secretive nature of Wakandan culture would also make it very difficult for the Skrulls to get into Wakanda, as the aliens would have no knowledge of the traditions they'd need to appear to honor.

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Of all the Avengers, then, there are really only two who could potentially be Skrull impostors: Black Widow and Falcon. The rest can safely be dismissed, for a wide range of reasons. For some, their being a Skrull would distort the MCU's ongoing narrative far too much, while for others it just wouldn't fit with the story we've seen build up over the course of the last decade. Of course, the truth is that we don't actually know that Captain Marvel will actually be the trigger for a "Secret Invasion" film at all. It could just as easily be "Secret Invasion," blending the Kree-Skrull War with a more recent comic book plot. We likely won't find out more until next year.

More: Captain Marvel Theory: It's Actually The MCU's Secret Invasion

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