***This post contains spoilers for every Marvel Cinematic Universe movie, including Black Panther, so proceed with caution!***
We're about a month away from Avengers: Infinity War, a movie the Marvel Cinematic Universe has been building to for almost a decade.
Other than who's going to die (cough Loki), the last big mystery going into Infinity War is how Thanos, the Mad Titan, will get ahold of the Infinity Stones.
Even if you've been sort of half-following the Marvel movies, you probably know what that Thanos wants to complete the Infinity Gauntlet — basically a big magic glove that needs six magic stones to fully power it.
The first time we see Thanos put on the gauntlet is during a post-credits scene in Avengers: Age of Ultron.
So far, after 18 movies, we have come across five of the six stones. The sixth, the Soul Stone, is still missing. The question becomes: where is the Soul Stone?
Short answer: It's in Wakanda. We'll walk through why, but first, let's rule out another popular theory.
Obviously, fans are obsessed with the stone's location. The most prominent theory is the "T.H.A.N.O.S. theory" — that Thanos's name is actually an acronym for the location of all the stones.
The "T.H.A.N.O.S. theory" seems to point in the direction of Heimdall from the Thor films being the "H" and having the Soul Stone. Which seems like it makes sense.
Also, during Thor's vision in Age of Ultron (that totally wasn't just an Infinity War trailer), Heimdall is blind.
But other than that, Heimdall's powers don't really line up with the properties of the Soul Stone.
Heimdall (or anyone) secretly being an Infinity Stone doesn't also really fit the pattern of how the Marvel films introduce Infinity Stones, though. First up was the Space Stone.
The next stone introduced was the Mind Stone.
Then there's the really weird sorta-stone, the Aether.
The Infinity Stone we know the most about is the Power Stone.
And finally, we've got the Time Stone.
Infinity Stones are usually introduced first by their containers. They also appear to have the ability to affect their environments, like the weird glitchy car park in Thor: The Dark World.
Or like when the Scepter starts to infect everyone's minds when they're onboard the Helicarrier in The Avengers.
Heading into Infinity War, we've got a stone with the Asgardians, another in the Vision's head, one with the Collector, one on Xandar, and one in Manhattan.
In the Infinity War trailer, Thanos is only shown with the Power Stone and the Space Stone. RIP Xandar and the Asgardians, I guess.
And it looks like the Black Order, Thanos's goon squad, will strip Vision of his Mind Stone.
We also know from the Infinity War trailer that Thanos goes to Wakanda.
When Thanos is shown fighting Cap, the same two stones are in his gauntlet. It's safe to assume there's a reason Thanos goes to Wakanda. Like, you know, to get an Infinity Stone.
Another thing to keep in mind is that every movie in the Marvel Cinematic Universe is either directly related to S.H.I.E.L.D. and the Avengers or has an Infinity Stone in it.
Alright, cool, how are you doing? Everyone still with me here? All of this brings us to Black Panther.
And so far there has been only one thing in the MCU that comes close to matching the description in the comics of the Soul Stone: vibranium.
It would make complete sense that the Soul Stone's container was the vibranium that crashed in Wakanda.
You might be saying to yourself, "But what about the color?" The vibranium energy in Wakanda is always shown as a bluish-purple.
The vibranium meteorite being the Soul Stone's container would also explain the mutated flowers in Wakanda that are used during the heart-shaped herb ceremony.
In this scene, T'Challa has literally been stripped of all of his powers, inside of a pocket dimension, accessing the memories of his dead father.
Also, in this scene, T'Challa comes across Bast, the Wakandan panther god.
One of the major themes of the MCU is that ancient religions were based on alien races. It would actually make less sense if Bast turned out to be a real deity and not an alien life form.
It would also create an interesting parallel between Wakandan scientists like Shuri and Western scientists like Howard Stark.
Anyways, that's my theory. Thanos is headed to Wakanda to get the Soul Stone.
(That and Loki is totally not surviving Infinity War.)
Ryan Broderick is a senior reporter for BuzzFeed News and is based in New York City.