A new theory suggests the Hulk is actually a Skrull impostor in the MCU, explaining Bruce Banner's strange behavior in both Thor: Ragnarok and this year's Avengers: Infinity War. The shapeshifting race known as the Skrulls are finally becoming part of the Marvel Cinematic Universe next year, with Captain Marvel loosely inspired by the Kree-Skrull War. Most viewers are expecting this to be setup for a future "Secret Invasion" plot, which may even means shapeshifting aliens have already secretly replaced some of the MCU's heroes and secondary characters. As a result, all attention is currently focused on the major character arcs; anybody who's acting out of character could potentially be a Skrull.

According to Mark Ruffalo, Marvel is partway through a three-film arc for the Hulk, one that kicked off in last year's Thor: Ragnarok, continued on through Avengers: Infinity War, and will culminate in next year's Avengers 4. But something about this arc seems to be striking an off-note with viewers, to the extent that some are already theorizing Banner has secretly been replaced by Loki.

Read More: Infinity War Theory: Loki Was Posing As Bruce Banner

Over on Reddit, one attentive fan has come up with another possible explanation. He argues that the Hulk has indeed been replaced - but not by Loki. Instead, he suggests that the Bruce Banner we've seen since 2015's Avengers: Age of Ultron is actually a Skrull impostor. Let's take a look at the evidence, and assess how likely this theory is.

Bruce Banner is Seriously out of Character In Thor 3 & Avengers 3

The Hulk of Thor: Ragnarok was very different to the rampaging behemoth we've seen in the MCU to date - so much so that he'd essentially developed a character and personality of his own and learned to speak. When Thor eventually got Hulk to transform back into Banner, we learned that the Hulk had taken the steering wheel for the last two years. That was used to explain why Bruce seemed more than a little flaky and disoriented, to the extent that even Thor felt he seemed out of character. On the face of it, it seemed to be little more than an example of Taika Waititi's sense of humor; but there may well have been more to it than that.

In Avengers: Infinity War, the strangeness simply increased. The Hulk suffered a brutal beat-down at the hands of Thanos, before being cast to Earth - and changing back due to the trauma of it all. Curiously, though, Bruce actually remembered everything he'd experienced as the Hulk - and even knew things about Infinity Stones he had no reason to know. That contrasts with every other transformation, including in Thor: Ragnarok, where Bruce typically can't remember anything he did as the Hulk. The rest of the film controversially avoided Bruce turning into the Hulk again at all, with the two personalities appearing to be in conflict.

Promotional images for Avengers 4 have teased that the Hulk is about to go through another major change in status quo, adopting the so-called "Professor Hulk" persona. This version of the Hulk seems to be less bulky, and thus likely not quite so physically strong. Clearly, we're expected to believe the two personalities are in a state of war, and they'll ultimately blend into one being; viewers seem to be finding that idea unpersuasive, however, and are instead suggesting other alternatives.

Related: Did Marvel Change Hulk's Story In Avengers: Infinity War?

Hulk Becoming A Skrull Has Comic Book Precedent

It's commonly believed Captain Marvel will introduce the Skrulls as setup for the famous "Secret Invasion" plotline. In the comics, this arc revealed that the Skrulls had been quietly collecting superheroes over the course of years, capturing and replacing them with their own impostors. Marvel made a conscious decision to avoid having any of the high-profile heroes be replaced; it was felt that would detract from major arcs like "Civil War." If the MCU is indeed heading for a "Secret Invasion" plot, then we can reasonably assume Marvel Studios will exercise similar logic. Titular heroes like Captain America, Thor, and Iron Man are probably safe, just because their character arcs are too integral to the MCU's momentum. But secondary Avengers, ranging from the Hulk to Black Widow to Scarlet Witch, could actually have been replaced.

Interestingly, sometimes Skrulls become absorbed in the identities they've assumed, and actually forget that they're impostors. That's especially the case when replacing more complex people - including those who suffer from a form of multiple personality disorder. So if the Hulk has been replaced by a Skrull, he may not be aware of it.

In the comics, the Skrulls can duplicate the powers of superhuman beings, but it's difficult for them to do so. What's more, unpredictable powersets like the Hulk's - a being whose strength grows in proportion to his rage - would likely be even harder, so a Skrull version of the Hulk would actually be weaker than the normal one. That would fit neatly with the Hulk's near-defeat at the hands of Thor, his difficulty when it came to handling Fenris, and the beat-down he suffered at the hands of Thanos.

Page 2 of 2: How The Hulk-Skrull Theory Fits the Ongoing Story of the MCU

How A Hulk-Skrull Fits Into The MCU

Of course, the real question is how well this fits with the MCU's ongoing narrative. At the beginning of Thor: Ragnarok, the Hulk has been missing for two years. That means the Skrulls could conceivably have captured him shortly after the end of Avengers: Age of Ultron. In that Reddit post, it's suggested the Hulk attempted to break orbit in the Quinjet, and the Skrulls noticed him. Another possibility, though, would be that the Skrulls were monitoring the Battle of Sokovia, and realized one Avenger was leaving in a Quinjet, presumably abandoning the rest of the Avengers. They intercepted the Quinjet - perhaps near Fiji, where S.H.I.E.L.D. lost track of the plane.

The Skrulls would conceivably then be able to spend quite a while working on the Hulk, exploring his DNA and trying to duplicate his powers. Only when they were satisfied would they have begun considering how to send their replacement back to the Avengers. But why would they send their Hulk to Sakaar? It may be that they deduced there was a solid chance Thor could turn up here, given Sakaar appears to be at the heart of a wide array of wormholes. As the Redditor points out, there's evidence in Thor: Ragnarok that the Hulk hasn't been the Grandmaster's Champion for long; his face still hasn't been added to Grandmaster's statue commemorating his Champions.

The Redditor suggests a subtly different variation on this, though; that the Hulk isn't the only Skrull impostor in Thor: Ragnarok. The theory suggests Skurge is a Skrull as well, and his mission was to get Thor to Sakaar. He then switched sides to learn about the potential new threat of Hela. At the end of the film, Skurge thus sacrifices himself in order to ensure the main Skrull operative, the Hulk, is successfully embedded in the Avengers. It's a rather more involved development of the theory, and an attractive one in that it removes the element of chance from this Skrull scheme.

Is The Hulk-Skrull Theory Plausible?

While it's an interesting theory, this one doesn't seem terribly likely. For one thing, this three-film character arc for the Hulk is clearly evocative of the Peter David run, with some scenes lifted almost perfectly from Incredible Hulk #376. It seems more reasonable to assume Marvel is setting the Hulk and Banner personalities in conflict. By that reading, the slightly out-of-character Bruce Banner in Thor: Ragnarok simply reflect Taika Waititi's more humorous style, and Banner's strange ability to remember what happened to the Hulk in Avengers: Infinity War is just a case of plot convenience.

Secret Invasion actually faced Marvel Comics with a difficult choice. On the one hand, they understandably wanted some major characters to actually be Skrull impostors, if only for dramatic effect. At the same time, though, Marvel didn't want to damage the character arcs that had been central to the last few years' worth of stories. That was why they didn't use "Secret Invasion" to reveal Tony Stark had been a Skrull impostor during Civil War. While that story had damaged Iron Man's popularity among comic book readers, it would have been far too convenient a solution. Likewise, Marvel avoided using the Skrulls to resurrect Captain America, who'd been killed off in the aftermath of Civil War. Marvel Studios will face the same problem if they do a Skrull invasion; they'd risk weakening the dramatic and narrative effect of the last few films. It's unlikely they'd retcon an entire character arc in this way.

Perhaps the one key takeaway from this theory, though, is that some fans don't seem happy with the Hulk's arc in Avengers: Infinity War. We've already had theories that the Hulk is actually Loki; now we have another, that he's a Skrull impostor. There's clearly a lot of dissatisfaction with how Avengers: Infinity War handled the Hulk, and that will likely give Marvel cause for concern. Hopefully, the final film in this loose Hulk "trilogy" will bring the story to a satisfying conclusion.

More: Avengers 4 Should Keep One Character Dead

Source: Reddit, via CBR

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