Avengers: Infinity War solved a surprising mystery from the MCU

It's a question fans thought they might never get the answer to - until now

*WARNING: MAJOR SPOILERS FOR AVENGERS: INFINITY WAR*

Avengers: Infinity War has been promised to fans as the "most ambitious crossover event in history": the Avengers meet the Guardians, Black Panther flings the gates of Wakanda open to the world.

Much of the thrill of this cinematic event has been in the gathering of the MCU's favourite characters to face off against one major villain: Thanos, in relentless search for the six Infinity Stones needed to complete the Infinity Gauntlet, and thus acquire control over the entire universe.

However, there was one rather surprising cameo that the film managed to sneak in, finally solving a mystery that's been hanging around since 2011's Captain America: The First Avenger. One more warning: SPOILERS AHEAD.

In a move pretty much no one could have guessed, it turns out Gamora held the secret to the so-far missing location of the Soul Stone, with Thanos having sent her on a mission to retrieve it years before, when she was still in his servitude.

With Nebula's life in the balance, Gamora agreed to take Thanos to its location, a planet called Vormir. Which appears to be home only to one soul: drifting out of the shadows like one of Harry Potter's Dementors, it's Red Skull that arrives to welcome them. An individual we last saw when he was catapulted through a wormhole at the end of The First Avenger.

Red Skull, in the 1940s, was originally one Johann Schmidt - a Nazi officer who founded the first incarnation of HYDRA - who attempted to use the Super Soldier Serum on himself and was left horribly disfigured - the result being his namesake red, skull-like face.

Schmidt was also, like all pop culture Nazis, obsessed with the weaponisation of occult objects, pursuing the Tesseract as a power source for Nazi weaponry - an object later revealed to contain the Space Stone.

As Guardians of the Galaxy went to show, it's wildly inadvisable for one person to hold an Infinity Stone with their bare hands, which is exactly what Schmidt tried to do; the result catapulted him into the wormhole, with Infinity War revealing (at least part of) his soul ended up on Vormir.

The character is here no longer played by Hugo Weaving, who'd previously distanced himself from making a reappearance in the MCU, but The Walking Dead's Ross Marquand.

He now describes his role as a keeper for the Soul Stone - his "curse" - though how exactly he landed the job isn't quite made clear. So, Infinity War certainly answers the great mystery of what happened to Red Skull, but it does pose a couple of additional questions in the process.

Avengers: Infinity War is out now.

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