After the events of Doctor Strange, and the introduction of the penultimate Infinity Stone, the quest began to locate the final stone. Could it show up in Spider-Man: Homecoming? What about Black Panther? Or, has the final stone been hiding in plain sight this whole time?
Now, we already have the Space Stone (Tesseract), Power Stone (Orb), Mind Stone (Vision’s head), Reality Stone (Aether) and Mind Stone (Eye of Agamotto). The last one remaining, the Soul Stone, might have a plausible location thanks to the following theory being kicked around the internet:
The Soul Stone is hiding in Heimdall’s eyes.
The theory comes from a Comicbook.com contributor who suggests that when Odin gave Heimdall his legendary vision, he did so using the power of an Infinity Stone. It would also explain the orange glow from Heimdall’s peepers, and that quick remark by the Norse God in Thor: The Dark World:
“From here I can see nine realms and ten-trillion souls.”
Sure, that seems like a pretty innocuous statement, but then look at the wording. Was Marvel laying some breadcrumbs by using the word “soul?” Kevin Feige and the minds behind the Marvel Cinematic Universe are always two steps ahead of everyone else, so it’s completely within the realm of possibility that they planned for Heimdall’s eyeballs to house the last remaining Infinity Stone.
There is one counterpoint to be made. In the post-credits scene for The Dark World, we see Lady Sif and Volstagg drop off the contained aether with the Collector since it wasn’t safe to keep two Infinity Stones on the same planet. With The Tesseract already on Asgard, why would Odin permit the Soul Stone to also be in the same realm? Perhaps his ego just got in the way, or he wished the identity of the Soul Stone to remain a secret. Maybe we get our answer when Thor: Ragnarok is released next year.
Although there are inconsistencies with the new Soul Stone theory, the signs do seem to point towards Heimdall’s oculars being the hidden location. Take, for example, Idris Elba’s cameo in Avengers: Age of Ultron. During Thor’s vision, Heimdall showed up, but something was noticeably different. The orange hue in his eyes was gone and he was blind. After letting Thor know that the God of Thunder killed them all, it was clear Thor messed up in a big way during Ragnarok, which caused Heimdall to lose his vision in the process. So, while Thor is out gallivanting with Hulk, Thanos might have just enough time to sneak in and steal the stone (and Heimdall’s powers in the process).
So, only the minds behind the MCU know what the future holds for Heimdall and his magnificent eyes. However, a strong connection to the massive Infinity Stone storyline would finally allow Idris Elba to shine! Feasibly, Heimdall could be the first hero to go toe-to-toe with Thanos (although it probably wouldn’t end well for him!). Whatever the case, we’re sure to get a clear picture of what the future holds for the Infinity Stones when Thor: Ragnarok is released next year on November 3rd. With Thor on his own quest, it would seem logical that Heimdall unleash the power of the Soul Stone to protect Asgard, an act revealing the stone’s location to Thanos, who would hastily and violently complete his quest of seemingly predestined collecting!