2019's Captain Marvel will see the titular hero face off against the alien race known as the Skrulls, and most viewers are expecting this to set up the Secret Invasion plotline. The film is set in the 1990s, with Brie Larson's titular hero plunged into the MCU's version of the Kree-Skrull war. A story written by Roy Thomas back in the '70s, the Kree-Skrull War saw the millennia-old conflict between two powerful alien races spill over onto the Earth. Our planet was essentially the cosmic equivalent of some Pacific Island during World War II.

While the Kree have existed in the Marvel Cinematic Universe since 2014's Guardians of the Galaxy, this will mark the MCU debut of the Skrulls. One of Marvel's most famous alien races, the Skrulls are shapeshifters who use their powers to infiltrate other worlds, and weaken them from within. They're every bit as militant as the Kree, and frankly are even more dangerous - when Skrulls are around, it's impossible to know who to trust. They've even learned to duplicate superhuman powers.

Of course, the more exciting question is just what this means for the wider Marvel Cinematic Universe. Marvel is well known for playing the long game, and audiences are primed to expect a major intro like this to be the setup for something even better. Now, fans are looking at the possibility that Captain Marvel  is setting up the Secret Invasion plot.

The Skrulls Must Be Setting Up The Secret Invasion

Secret Invasion was Marvel's summer event of 2008, and writer Brian Bendis had been building up to it for over a year. The concept was a chilling one; the Skrull homeworld had been destroyed years ago, and the aliens had developed a religious obsession with Earth. To that end, the Skrulls had begun systematically infiltrating the Earth's defenders. Skrulls had slipped into the armed forces, the security services, S.H.I.E.L.D., and they'd even wormed their way into the world's superhero community. The Skrull princess, Veranke, personally infiltrated the Avengers as Spider-Woman.

The Avengers first realized the Skrulls were on Earth when the Hand's leader Elektra was killed - and her body transformed back into her Skrull form. Analysis of the Skrull's body led the heroes to realize there was no way they could detect these impostors; literally anyone, anywhere, could be a Skrull. That meant the Avengers were faced with one terrible question: Who do you trust? Bendis enjoyed building up a sense of paranoia in the build-up to the main event, then launched the invasion at breakneck speed, right down to a crashed spaceship full of superhero impostors that arrived in the Savage Land.

Strangely enough, until Secret Invasion few Marvel Comics had really exploited the shapeshifting potential of the Skrulls. There had been occasional flashes of brilliance - a long-running story in which a Skrull impostor fell in love with the Human Torch, or an X-Men plot in which the Skrulls had secretly taken over the Shi'ar Empire and even replaced Professor Xavier. But, on the whole, the Skrulls had simply been used as just another alien race. It took Brian Bendis to really develop the aliens to their full potential, revealing how dangerous a race of shapeshifters could actually be.

Related: 15 MCU Characters Who Could Be Skrulls In Disguise

When Kevin Feige announced that the Skrulls were coming to the MCU, he knew full well that every comic book reader would immediately think of Secret Invasion. There are some clear long-term implications of a Skrull presence on Earth, too. The Skrulls could have infiltrated S.H.I.E.L.D. and Hydra for decades, and they could even still be around in the present-day MCU. Many fans have theorized that Captain Marvel could see the destruction of the Skrull Homeworld, setting the scene for a full-on Secret Invasion movie.

Page 2 of 2: Could Captain Marvel Actually BE The Secret Invasion?

Could Captain Marvel Actually Be The Secret Invasion?

But does Captain Marvel really have to set up for Secret Invasion, or could it instead be the main event? It's important to remember that Marvel doesn't do straight comic-to-screen adaptations. In an interview discussing Avengers: Infinity War, Joe Russo pointed out that "the Marvel Cinematic Universe is not the Marvel comic book universe." As he explained, "As a comic book fan, I think it’s fun to take elements from the books that I identify with. But if I want a literal interpretation, I’ll just read the book."

That pattern runs throughout Marvel's movies. In Avengers: Age of Ultron, it is Tony Stark who creates the titular android, not Hank Pym. In Captain America: Civil War, the idea of some sort of superhuman registration act is blended seamlessly with the ongoing story of the Winter Soldier. Most recently, Avengers: Infinity War may have ended with a scene lifted straight from the comics, but the journey to that point was radically different. Marvel only ever takes loose inspiration from the comics; they honor the overarching themes and high-level concepts, rather than simply transposing the story from the pages to the screen.

Related: Avengers: Infinity War's Ending Was Very Different In The Comics

Given that's the case, it wouldn't be a surprise to see Captain Marvel tell the MCU version of the Secret Invasion plot. The Kree-Skrull War could easily form the backdrop for this story, perhaps with the Skrulls seeking a new homeworld in the aftermath of a catastrophic Kree attack. The main story would then be about the Skrull infiltration on Earth, with Carol Danvers, Nick Fury, and young S.H.I.E.L.D. agent Phil Coulson desperately working to defeat the aliens.

Why Captain Marvel Would Be A Better Secret Invasion Than The Avengers

The Secret Invasion comic book arc is fondly remembered, but it drew heavy criticism at the time of its release. The strongest criticism was that the comic didn't actually honor its central concept. The story proceeded at a breakneck pace, revealing one Skrull impostor after another, rather than focusing on the sense of intrigue and suspense. The scale of the adventure was a little too vast, and as a result, the story didn't have time to breathe or explore the emotional impact of learning your friend, colleague, or even lover was actually a Skrull. Those resonant character moments were left for the tie-ins, resulting in an underdeveloped central story.

An Avengers movie would inevitably suffer the same fate. Avengers films are becoming sprawling, global adventures, drawing in every one of the world's heroes to date. Just as in the comics, an Avengers: Secret Invasion film wouldn't have the time to explore what it really feels like to be betrayed in this way. You need a deeper, more personal story than that, one starring a single character - like Captain Marvel.

Another major issue is that any Secret Invasion film would presumably be released well after Avengers 4. That movie is intended as the 10-year celebration of the MCU, a culmination of the last decade's worth of Marvel movies. Now imagine viewers learning that some of those arcs were never real in the first place, that prominent Avengers had actually been replaced by Skrull impostors, or that certain characters never actually died at all - only their doppelgangers did. The idea of Secret Invasion is an attractive one, but it risks actually causing damage to the narrative flow of the shared universe.

Related: Everybody Who Dies in Avengers: Infinity War

With the 90's setting of captain Captain Marvel, the movie is relatively standalone- outside of a few ties to Avengers 4. Thanks to this insulation, literally anyone can be a Skrull impostor. Any secondary character could actually be an alien, even crucial characters like Phil Coulson or Nick Fury. Captain Marvel has the freedom to explore this idea without doing any damage to the MCU's established ongoing story.

That doesn't mean Captain Marvel would have no impact, though. A Secret Invasion arc would explain Nick Fury's secretive nature. "The last time I trusted someone, I lost an eye," Nick Fury told Steve Rogers in Captain America: The Winter Soldier. That incident could actually be part of the Secret Invasion, with Fury trusting someone who turns out to be a Skrull. In response, Fury becomes withdrawn, withholding his trust from all but a select few. He becomes the secretive man we know and love in the MCU.

Finally, it's important to remember that Kevin Feige has suggested Marvel is moving away from its traditional "phases." The first three phases of the MCU have been characterized by a clear structure, with a narrative buildup in the individual films that comes to a head in a tentpole Avengers movie. It's easy to understand why Marvel is considering ditching this approach; as exciting as an Avengers film may be, working out the schedules for so many actors is a logistical nightmare. What's more, Feige seems to have gotten a little frustrated at the fact viewers are always trying to work out how a solo film fits into the next tentpole, rather than enjoying each movie as an individual film. While we'll inevitably get another Avengers film sooner or later, it wouldn't be a surprise to see that happen at, say, the 20th anniversary of the MCU. If that's the case, any momentum for a Secret Invasion plot would have been long since lost.

It's easy to understand why comic book lovers have assumed Captain Marvel will be set up for Secret Invasion, but Marvel may be wiser to simply go all the way and use the solo movie as their version of that plot. Rather than create another sprawling tentpole, the studio could instead fashion an intense story in which one hero struggles to work out just who she's able to trust.

More: Marvel Could Avoid Exploring The Fallout of Avengers: Infinity War

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