Red Skull may have secretly had knowledge pertaining to all six of the Infinity Stones, rather than just one. The MCU adaptation of Captain America’s greatest enemy in Marvel Comics is tied directly to two of the Infinity Stones, which are the most powerful known artifacts in the universe.

In Captain America: The First Avenger, Hugo Weaving’s Red Skull led HYDRA in pursuit of an ancient weapon referred to by him as the Tesseract. Through its immense, immeasurable power, Red Skull and Arnim Zola (Toby Jones) were able to use it as an energy source for HYDRA’s weapons. Though the Tesseract gave HYDRA’s forces a huge advantage, Captain America (Chris Evans) and his Howling Commandos were able to win in the end. As a result of their final battle, the Tesseract was lost in the ocean and eventually recovered by SHIELD. It was later revealed that the Tesseract – known in the comics as the Cosmic Cube – is actually the Space Stone, one of the six Infinity Stones sought by Thanos (Josh Brolin).

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Red Skull lost the Tesseract, but became associated with another Stone decades later in Avengers: Infinity War. Through a shocking reveal, it was made clear that Red Skull was never killed; he was transported to the planet Vormir. Now played by Ross Marquand, Red Skull was made the guardian of the elusive and mysterious Soul Stone. It became Red Skull’s job to explain the rules of the Stone to those who came for it. In Infinity War, the Soul Stone was retrieved by Thanos, who had to give up the person he loved – Gamora (Zoe Saldana) -- to claim it. The former Captain America villain and HYDRA leader returned in Avengers: Endgame to give the same explanation to Hawkeye (Jeremy Renner) and Black Widow (Scarlet Johansson). Unfortunately for the Red Skull, he couldn’t take the Stone for himself, but it’s possible that prior to his arrival on Vormir, he already knew about both Stones - and the other four.

How Red Skull Knew About The Tesseract

Red Skull with the Tesseract

Marvel isn’t specific about how Red Skull knew about the Space Stone in Captain America: The First Avenger, but it would seem that his hunt for the Tesseract grew out of his interest in history. Possibly by researching ancient weapons, Red Skull may have come across some old Norwegian texts that clued him in about the Asgardians. Centuries ago, Odin (Anthony Hopkins) left the Space Stone on Earth, and if records of that were left by those who had witnessed this, Red Skull could have read about it and discovered its existence. It could be that the source of this information also shed some light on the nature of the Tesseract, and the notion that’s it just one of a handful of cosmic weapons.

Red Skull Knew About The Scepter's Importance

Loki holding the Scepter in the opening scene of The Avengers

In Avengers: Age of Ultron, HYDRA’s Baron von Strucker (Thomas Kretschmann) used Loki’s Scepter to perform experiments on Scarlet Witch (Elizabeth Olsen) and Quicksilver (Aaron Taylor-Johnson). A recently published Marvel book, The Wakanda Files, included a memo written by Strucker for Dr. List (Henry Goodman) detailing why HYDRA chase Sokovia for its base, and it also provides notes on the Scepter. Apparently, Strucker knew it had “untold potential” and also stated that Red Skull was aware of it. According to Strucker, Red Skull believed it was “left for us by the Gods”.

It’s important to keep in mind that Red Skull held a similar opinion of the Tesseract, which he called “the jewel of Odin’s treasure room”. The fact that Red Skull considered both the Tesseract and the Scepter to be divine artifacts suggests that he may have suspected that there was a connection between them. It could be that Red Skull knew that the Scepter housed the Mind Stone, and that it and the Tesseract were part of a set. What’s surprising about this is that the Scepter didn’t find its way to Earth until 2012, so there’s some question of how Red Skull – a mortal human who had never left Earth – could know about a weapon that dwelled in outer space.

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Infinity War Already Showed Red Skull Was Aware Of The Soul Stone

Red Skull in Avengers Infinity War

It would make sense that during Red Skull’s time on Earth, he learned about more than just the Space and Mind Stones. The Soul Stone must have been a part of Red Skull's research, otherwise how was he able to clearly articulate the rules in Infinity War and Endgame? The Marvel Cinematic Universe Visual Dictionary reveals that when Red Skull raided the tomb in Norway and acquired the Tesseract, he got his hands on “an earthly version” of the Book of Yggdrasil, an Asgardian text that Odin had in his possession in Thor: The Dark World. In the movie, it was shown that the book held many secrets of the universe and its creation. Odin also used the book to warn Thor about the Aether (better known as the Reality Stone).

If Red Skull’s copy of the Book of Yggdrasil shared all the same information, then he would of course know about the existence of the Reality Stone. In addition to that, the book may have laid out the rules of the Soul Stone for him. Plus, the book being packed with all this knowledge would make sense of how Red Skull knew about the Mind Stone. If he was able to learn all this from the Book of Yggdrasil, it’s possible that he could have discovered even more than that. If it included details about these three Stones, there may have been evidence of the Time and Power Stones stored in the book somewhere as well.

HYDRA Knew About All Of The Infinity Stones (But Not What They Did)

Red Skull in Avengers: Infinity War

Thanks to the Book of Yggdrasil and Red Skull’s independent research, it appears that HYDRA could have had access to information regarding all six Infinity Stones. However, Avengers: Age of Ultron and Captain America: The First Avenger indicates that no one within HYDRA – Red Skull included – understood how to properly utilize their capabilities. They tried to make use of them as energy sources, but didn’t use them as effectively as Thanos did in Avengers: Infinity War.

It’s also likely that Red Skull and HYDRA had no way of ever actively pursuing all the other Stones. Being in outer space, the Soul, Mind, and Power Stones were always out of Red Skull’s reach. It’s hard to imagine him acquiring the Reality Stone either. As for the Time Stone, it was on Earth, but taking it from the Ancient One (Tilda Swinton) would have been no simple task. However, Red Skull was an ambitious individual and its hard to say if his thirst for power would have extended beyond the Space Stone if he hadn’t been defeated by Captain America during World War II.

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