The Infinity War is almost upon us, and as Marvel fans eagerly await the release of the new Avengers movie, there is one question on everyone's mind: Where is the Soul Stone? The Marvel Cinematic Universe has been slowly teasing out the six Infinity Stones for a full decade with dozens of blockbuster movies, and it has all been leading up to this. But one stone is still puzzling even the most hardcore Marvel fans. The new Avengers: Infinity War Soul Stone theory makes a very convincing case that we have seen the final Infinity Stone already... as a part of a very familiar Marvel side character.
Before we get all up in this location theory, let's have a quick refresher on the Infinity Stones. Basically, these are six all-powerful galactic gems that can grant unlimited power to anyone who holds all six at once. We've already seen the power of five of these stones in past MCU movies: the Space Stone wreaked havoc in the first Avengers movie, the Mind Stone was at the center of Age of Ultron, the Power Stone was what everyone was after in Guardians of the Galaxy, the Reality Stone made things difficult for Thor in The Dark World, and Doctor Strange made use of the Time Stone in Doctor Strange. But not all of these Infinity Stones were referred to by name in these movies — instead, characters referred to the vessels that held the stones.
The names of these vessels are actually the first part of the Soul Stone theory. Fans began to notice that the first letter of each Infinity Stone vessel may be spelling an important word: Thanos, the intergalactic warlord hunting them down and the main villain of Avengers: Infinity War.
If the Infinity Stone vessels are indeed spelling out Thanos' name, then that means that the Soul Stone must be hidden in something that begins with an "H." Got any guesses? Well, the main guess that fans have is not a thing, but a person. That's right — all signs point to Thor's all-seeing buddy Heimdall!
Why Heimdall? Well, not only does he fit the H-name requirement, but his eyes also just so happen to glow in the Soul Stone's signature color of orange. Plus, Heimdall has that unexplained power to see everything in the universe, and allow others to see through his eyes. Could that be the Soul Stone at work within him?
Not to mention, when Heimdall first appeared in Thor, he was wearing a golden suit of armor with what looked like an orange stone on his chest. That raised a few eyebrows back then, but now it seems even more important.
Convinced yet? When we last saw Heimdall, he was on board Thor's spaceship with the rest of the Asgardians who escaped their home world right before it exploded. If he does indeed have the Soul Stone in him, then that ship is crawling with Infinity Stones, since Loki also swiped the Space Stone before jumping on board.
We know from the Avengers: Infinity War trailer that Loki is going to hand over the Space Stone to Thanos relatively early in the movie, and that Thanos will have both the Space Stone and the Power Stone when he arrives on Earth. Here's where there could be a potential problem with the Heimdall theory: If Thanos boarded the Asgardian ship and got Loki's Space Stone, then why wouldn't he have also taken the Soul Stone from Heimdall if the seer does indeed have it?
That's definitely not a theory-breaking observation, though. Perhaps Heimdall found some way to escape the ship before Thanos arrived, or Thanos is still unaware of the Soul Stone's real location.
The other major Soul Stone theory is that the final Infinity Stone is in Wakanda, considering how prominently the country is featured in the trailers. Following the H-word theory, the best bet here would be the heart-shaped herb, which provides the Black Panther with his powers. The herb also transports those who eat it to a spiritual realm where they can commune with dead ancestors, which sounds very Soul Gem-y to me. But alas, Black Panther director Ryan Coogler confirmed the Soul Gem wasn't in Black Panther at all, and plus, Killmonger destroyed all the heart-shaped herb.
The Heimdall theory seems to be the most convincing one that Marvel fans have about the Soul Stone right now, so keep your eye on Idris Elba when Avengers: Infinity War hits theaters on April 27!