Perhaps the biggest question in all of the Marvel Cinematic Universe has finally been answered. For quite some time, fans have been wondering and theorizing about the location of the Soul Stone, the last unaccounted for Infinity Stone in the MCU, which Thanos desperately needs in Avengers: Infinity War. Now that the movie is in theaters the stone's location has been revealed and it was rather surprising.

Warning: major spoilers ahead for Avengers: Infinity War. Seriously, if you haven't seen it this is some monumental stuff, so if you don't want it spoiled, turn back now. What we come to learn is that Gamora, Thanos' favorite daughter, was at one point entrusted with discovering the location of the Soul Stone. She accomplished as much, but never told Thanos about it. She burned a map to its location, but after the Mad Titan revealed he was going to kill Nebula if Gamora didn't reveal the location, she caved. The Soul Stone was located on the planet Vormir.

The planet itself was pulled from the world of Marvel Comics. A fun little Easter egg for fans. But that wasn't nearly the biggest part of this massive mystery. Once Gamora and Thanos arrive at Vormir to retrieve the Infinity Stone, they are greeted by a cloaked figure who has been tasked with guarding the powerful object. This figure is none other than Red Skull. That's right! Easily one of the biggest and most unexpected reveals in not just Infinity War but the MCU overall is that the villain from Captain America: The First Avenger, long thought to be dead, is actually now the guardian of the Soul Stone.

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This was easily another one of the greatest mysteries in the MCU. Fans have wanted to know what happened to Red Skull for years and this was a pretty amazing way to bring him back. As Red Skull reveals to Thanos and Gamora, after attempting to wield the Tesseract for himself, he was banished to the cosmos and is now cursed with the knowledge of knowing where the Soul Stone is and what it takes to acquire it, but he can't ever use its power for his own gain. He is not powerful enough to take on its might.

Thanos, on the other hand, is plenty strong and Red Skull has to explain to the villain how to obtain the Soul Stone. This particular Infinity Stone requires a sacrifice in order to prove the one trying to use it is worthy. Not just any sacrifice, mind you. The being must sacrifice the one they love most in the universe. In the case of Thanos, that happens to be Gamora. In a gut-wrenching moment, Thanos sheds some tears of pain over the decision, but he indeed kills his adopted daughter Gamora in order to get his hands on the Soul Stone. He throws her over the cliff and, to prove that he actually finished the job, we see her bleeding body on the rocks below. It's brutal by MCU standards, but proves just how far Thanos is willing to go on his quest.

There were countless theories online over the last year or so proposing where the Soul Stone may be located. Prior to the release of Black Panther, many thought it was perhaps hiding in Wakanda. Nobody was even close. Two huge Marvel mysterious were wrapped up in one huge, surprising and emotional sequence within Avengers: Infinity War.

Ryan Scott