Warning: SPOILERS for Black Panther are ahead!
The Avengers established that Thanos would be the overarching antagonist of the Marvel Cinematic Universe, but it wasn't until Thor: The Dark World confirmed that the objects that his comic book counterpart craves, the Infinity Stones, also exist in this continuity. As of Doctor Strange, five Infinity Stones are accounted for, leaving the Soul Stone as the only one of these ancient, powerful artifacts that hasn't been officially introduced yet. For a while, it was speculated that the Soul Stone might show up in Thor: Ragnarok, and when that didn't happen, some believed that we might see the orange rock in Black Panther. Well, T'Challa's standalone movie finally hit theaters this weekend, and while it's established itself as a critical and commercial powerhouse, one thing it does lack is an Infinity Stone. So with three months to go until Avengers: Infinity War, unquestionably Marvel's biggest movie yet, the question remains, just what's going on with the Soul Stone?
Because Avengers: Infinity War will follow Thanos trying to obtain the six Infinity Stones so he can become the most powerful being in the universe, one would imagine that we'll see the Soul Stone in the movie, even if Thanos doesn't get his hands on all of them. After all, although Infinity War and Avengers 4 will still be closely connected, they're considered to be two "distinct" movies, so we can't assume that Avengers 4 will keep focusing on the Mad Titan's quest for invincibility. In any case, it's possible that Thanos has possessed the Soul Stone this entire time.
When it was revealed in Avengers: Age of Ultron that Loki's scepter contained the Mind Stone, many appropriately pointed out that Thanos loaning the Asgardian God of Mischief an Infinity Stone was a weird decision, even if the endgame was to retrieve another Infinity Stone. But if Thanos already had the Soul Stone sitting in his vault or junk drawer, then at least by losing the Mind Stone, he wouldn't be entirely without Infinity Stones, so giving it to Loki would have been more of a calculated risk. Admittedly, the Infinity War trailer only showed the Mad Titan with the Space and Power Stones in the Infinity Gauntlet, but perhaps he has it tucked away elsewhere and will only join it with its "siblings" when he gets the Mind, Reality and Time Stones.
However, even though Black Panther didn't show the Soul Stone, we shouldn't rule out that it's in Wakanda. The Avengers: Infinity War trailer showed that the technologically-advanced African nation will be the site of one of the movie's big battles, with T'Challa, his Avenger allies and Wakanda's finest warriors engaging Thanos' monstrous hordes. Publicly, vibranium is Wakanda's most prized resource, and now the whole world knows it thanks to T'Challa deciding to reveal his country's true nature to the rest of the world. But perhaps the Soul Stone is something that only a select few in the Wakandan government know about.
As shown twice in Black Panther, when an individual inherits the Wakandan throne, they take the Heart-Shaped Herb to gain enhanced physical abilities and go on a journey to the spirit realm, where they can communicate with the dead. While not directly confirmed in Black Panther, if these visions are anything like they are in the comics, then T'Challa, Killmonger and the past Wakandan monarchs were actually speaking with spirits rather than just hallucinating. So in the MCU, it's not implausible that the Soul Stone is responsible for this supernatural experience, and hence why Thanos has sent his army to attack Wakanda.
Of course, these are just two of the theories floating around concerning the Soul Stone's location. Despite its absence from Thor: Ragnarok, some are still speculating that the Soul Stone resides within Heimdall and is the reason the Asgardian can see across the Nine Realms. Maybe Avengers: Infinity War will show Thanos finding it on a world we haven't visited in the MCU yet. It's even possible that the Soul Stone was moved to a different reality at some point, like the Quantum Realm or the Dark Dimension. Wherever it is, with Avengers: Infinity War bringing the Infinity Stones arc to a head, and Phase Three wrapping up next year with Avengers 4, we're going to going to see the Soul Stone very soon, and it will be nice to finally see what this particular Stone is capable of doing in the MCU.
With Black Panther now screening for the masses, Avengers: Infinity War is the next MCU movie up, hitting theaters on May 4.
Where Do You Think The Soul Stone Is?