When Thanos snapped his fingers at the cliffhanger ending of Avengers: Infinity War, did he actually consign half the life in the universe to oblivion? Or, instead, will next year's Avengers 4 reveal that the victims of the "snap" - including heroes like Spider-Man, Star-Lord, and Black Panther - were transported into the Soul World, a realm existing inside the Soul Stone, as many have theorized.

The location of the Soul Stone, last of the six Infinity Stones, was one of the abiding mysteries of the MCU. It was finally revealed in Avengers: Infinity War, with Thanos learning that it was hidden on the distant world of Vormir. He sacrificed his daughter Gamora in order to obtain the Soul Stone, but barely used its power. Although tie-in comics had described the Soul Stone as "the biggest threat" of all the Infinity Stones, the film itself didn't even hint at what the Soul Stone could do. Thanos acquired it late in his quest, and the only clear thing he used it for was to work out which Doctor Strange was real, and which were illusions.

Related: Every Time Thanos Used The Infinity Stones In Avengers: Infinity War

Given the Soul Stone's actual role in Avengers: Infinity War was relatively underwhelming, it's hardly surprising that many viewers are speculating it will be particularly important in Avengers 4. A surprisingly common theory suggests that it could well be key to undoing the "snap" itself.

The Soul Stone Theory Explained

The fundamental problem of Avengers: Infinity War is that the film kills characters we know are due to returnSpider-Man: Far From Home is currently in production, a movie set "minutes after" the events of Avengers 4. Kevin Feige himself recently confirmed that Doctor Strange 2 is certain to happen, while director Scott Derickson dropped a curious hint that suggests pre-production could begin next month. There's also been substantial discussion about Black Panther 2, hardly a surprise given the film grossed over $1.3 billion worldwide and essentially forced the Oscars to set up a whole new award, "Best Popular Film." If three of the most important "snap" victims are set to return, it's reasonable to assume that all of them will do so. Although some Marvel figures are still trying to persuade viewers these deaths will last (most notably the Russo brothers), their attempts are in vain; Thanos's horrific act is clearly destined to be undone, just as it was in the comics. The only question is, how?

This is where the Soul Stone Theory comes in. According to this theory, Thanos didn't actually kill half the life in the universe at all; instead, they were consumed by the Soul Stone. In the comics, the Soul Stone is a sentient being in its own right, and has a voracious desire to consume the souls of living beings. Anyone unfortunate enough to be consumed by the Soul Stone winds up trapped within a realm inside the Soul, known as the Soul World. Importantly, it's quite possible to both escape the Soul World, and to be freed from it. The Soul Stone Theory suggests that the surviving Avengers will liberate their "deceased" colleagues from Soul World, take the battle to Thanos in one final fight, and then free the rest of the Soul Stone's victims too. Some even suggest that the original six Avengers will be the final sacrifices that lead the Soul Stone to release these victims; "A soul for a soul," as the Red Skull hinted.

It's a compelling theory, and at first glance it's strongly inspired by the comics themselves. What's more, the Soul World did indeed appear in Avengers: Infinity War. When Thanos snapped his fingers, his consciousness was briefly transported into the Soul World, where he spoke to the spirit of Gamora, the woman he had sacrificed to the Soul Stone. Given this is the case, the Soul Stone Theory has proved compelling enough to persuade many viewers

But is the Soul Stone Theory true - or is it instead something of a red herring?

Next Page: The Problems With The Soul Stone Theory

Avengers 4's Time-Travel Arc Makes The Soul Stone Theory Worthless

The fundamental problem with the Soul Stone Theory, though, is a simple one; it's unnecessary. The theory provides an answer to the question of just how these missing and deceased Avengers will return, but all the evidence strongly suggests Marvel is taking a different approach. Rather than explore the Soul World, they aim to use time-travel.

There's abundant evidence that Avengers 4 will be some sort of time-travel film, revisiting the events of a number of previous movies. A number of key set photos have shown scenes clearly set around the Battle of New York, an event that dates back to 2012's The Avengers. Zoe Saldana and Karen Gillen have been spotted in the costumes their characters worse back in 2014's Guardians of the Galaxy. And there are rumors that previously-deceased characters will be returning, including Frank Grillo's Crossbones. It's most likely that the Avengers will use the Quantum Realm to travel through time; that mysterious dimension was a focus of Ant-Man & the Wasp (with comments about "time vortexes"), and will return in Captain Marvel.

Related: Ant-Man & The Wasp Director Won't Rule Out Avengers 4 Time Travel Theory

Why would the Avengers be traveling through time? The logical reason is that they're attempting to rewrite history - specifically, to avert the events of the "snap." Avengers 4 isn't about undoing the "snap," it's about ensuring it never happened in the first place. Given that's the case, the Soul Stone Theory is pretty much irrelevant. What does it matter if Thanos's victims have been transported into the Soul World? Time will be rewritten, so they were never sent there anyway. There is no need for the Soul Stone Theory.

The Soul Stone Theory Doesn't Explain the Vision

The shooting schedule of Avengers 4 came to an end in December 2017, with scenes that seem to have involved both "snap" victims and survivors. Going by Instagram and social media posts, there's evidence that Anthony Mackie, Dave Bautista, Elizabeth Olsen, Evangeline Lilly, Pom Klementieff, Tom Holland and Samuel L. Jackson - all killed by Thanos - were in Atlanta around the same time. It looks as though this was for a major "return" scene, a mass resurrection of the dead heroes. But, crucially, there's one other actor confirmed to be on set at the time: Paul Bettany.

This is one resurrection that couldn't possibly be explained away by the Soul Stone Theory. Vision didn't die as a result of the "snap." Rather, he died when Thanos plunged his hand into the android's forehead and withdrew the Mind Stone. The "snap" could only happen because Vision was already dead. There's absolutely no way Vision's soul - if he even has one - is trapped inside the Soul Stone. So any resurrection scene logically has to involve something completely different, say, the Avengers traveling back in time and preventing Thanos killing him in the first place. Vision's return fits perfectly with the idea that Avengers 4 is about time-travel, but it can't possibly fit with the Soul Stone Theory.

The "Snap" Showed No Evidence of the Soul Stone's Influence

The Soul Stone Theory is both unnecessary to the plot of Avengers 4, and insufficient when it comes to explaining the resurrections. Crucially, though, it also doesn't fit with the details of the "snap" scene. VFX supervisor Dan Deleeuw recently told Screen Rant that his team originally considered a disintegration effect that involved all the different colors of the Infinity Stones, in order to show that the power of the six Stones was being united in this one horrific act.

"[It] made sense that all six stones are combined now, [so] what stones would... how would combining the stones make that happen? So does the Soul Stone go in and disintegrate their soul? And does the Power Stone disintegrate the body? And the Space Stone what actually moves the ash? And so early tests were combining all those different pieces and although it was kind of beautiful in a way, it just became too much, right? It became... if there was too much of a Soul Stone effect it looked like they were on fire when they were disintegrating, and the idea was like just back off and keep it simple."

Related: Avengers 3 & Ragnarok Made A New Infinity Gauntlet Plot Hole

In the end, the VFX team focused in on the Power Stone, creating an effect that's evocative of the death of The Collector's assistant, Carina, in Guardians of the Galaxy. Visually, then, if any one of the Infinity Stones is particularly responsible for the death of half the life in the universe, it's the Power Stone. In keeping with Deleeuw's comments, there's no hint of the Soul Stone's orange hue in the disintegrations.

What's more, the very fact Thanos entered the Soul World immediately after the "snap" works against the theory. He catches a brief glimpse of a realm that is barren and, apart from Gamora, completely devoid of life. There's no hint that other souls are transitioning into the Soul World. As far as Avengers: Infinity War is concerned, Gamora seems to be the only one trapped within.

Page 3 of 3: The Soul Stone's REAL Role In Avengers 4

Gamora in Soul World from Avengers Infinity War

There is One Person Inside the Soul Stone

After years of build-up, it would be disappointing if the Soul Stone were to prove largely irrelevant to the plot of Avengers 4. That's not the case, however, because the Soul Stone does contain one being trapped inside it - Gamora. Zoe Saldana has already confirmed that her character will return in Avengers 4, and James Gunn planned for her to play a major role in Guardians of the Galaxy Vol. 3. She may not have been one of the "snap" victims, but Gamora's story is far from over.

What's more, Avengers: Infinity War dropped an important hint as to how she could return. The Red Skull claimed that one soul could be traded for another; a being who loves Gamora could potentially sacrifice themselves in order to bring her back. Fortunately for Gamora, there are three beings who would probably be willing to do so:

Related: Why Disney Isn't Rehiring James Gunn For Guardians of the Galaxy 3

  • Star-Lord. By Avengers: Infinity War, the "unspoken thing" between Star-Lord and Gamora had blossomed into love, and Peter Quill was devastated at Gamora's death. There's no doubt he'd be willing to offer himself in Gamora's place. However, while this sacrifice would work in narrative terms, it's the least likely in light of Marvel's future plans. Chris Pratt is the franchise lead for the Guardians of the Galaxy, and he's already confirmed for the third film.
  • Nebula. The character arc between Gamora and Nebula has been a fascinating one; when the two were introduced in Guardians of the Galaxy, they were bitter foes. Guardians of the Galaxy Vol. 2 saw the siblings reconcile (after trying to kill one another a few times), and the relationship between them has since gone from strength to strength. It's notable that Gamora chose to tell Nebula alone that she knew the Soul Stone's location, indicating just how close the two now are. There'd be a beautiful sense of poetry in Nebula's sacrificing herself to bring Gamora back. What's more, the Russo brothers have insisted the "snap" survivors were all chosen for story reasons, and this would be a fitting one. Supporting this theory, Gillan's name is the only one of the main Guardians cast that has yet to be mentioned in reference to Guardians of the Galaxy Vol. 3. That could easily be because she doesn't survive.
  • Thanos himself. The Mad Titan's motives in Avengers: Infinity War were simply insane. Far from save the universe, he'll have plunged it into chaos. It's possible that, over the course of Avengers 4, Thanos will come to realize that he was wrong. In his own crazy way, Thanos did truly love Gamora; that's why the Soul Stone accepted his sacrifice. If Thanos were to decide it wasn't worth it, if he were to believe that his quest to restore balance across the cosmos had failed, then there's no question he'd be willing to sacrifice himself to bring Gamora back.

The most likely of these scenarios is that, towards the end of the film, Nebula will come to understand that she can offer herself in Gamora's stead. She will thus do so, sacrificing herself so that her sister can live. Regardless of who makes the sacrifice, though, it looks pretty certain that one will be made - and that the Soul Stone will be the basis of another emotional scene in Avengers 4.

More: Avengers 4: What Role Do Thanos' Snap Victims Play?

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