The biggest mystery of Avengers: Infinity War may already have been solved

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Over the past decade of Marvel movies we’ve seen five of the concentrated, reality-warping ingots feature in various movies, and we know Thanos needs all six of them to power his deadly Infinity Gauntlet. So far we’ve seen the Space stone, the Power stone, the Mind stone, the Time stone and the Reality stone, and they’re currently still scattered across the universe – so where could the final Soul Stone have been this whole time?

Well, we might just have an idea. For a while fans have hypothesised that the final Infinity stone will turn up in Wakanda, the fictional African nation introduced in Black Panther and which features quite heavily as a major battle location in the first Avengers: Infinity War trailer.

The thinking goes that Thanos will collect the first five Infinity stones earlier in the film (we see him with the Space and Power stone in the trailer) before facing the Avengers in their final (ish) stand in Wakanda – and now we might have spotted a piece of evidence as to where in T’Challa’s ends the Soul stone might have been hiding.

You see, a few years ago fans noticed that each of the hiding places or alternate forms assumed by the stones had something in common – the first letter of each location corresponded to a letter in Thanos's name.

Now, this could all be a coincidence (the “necklace” description of the Eye of Agamotto is pretty tenuous, after all), but it could also be a clever joke hidden inside the film by Marvel’s masterminds all this time. Thanos’s name has existed for decades in Marvel comics – but each of these Infinity stone-objects has been created or renamed for the films (for example, the Tesseract is based on the Cosmic Cube from the comics). Who’s to say Marvel couldn’t have been steering their naming to reflect the franchise’s Big Bad?

And if they have, we reckon we might know exactly what “H” the Soul stone is hiding within – Wakanda’s famed Heart-shaped Herb, a plant that when ingested gives T’Challa (Chadwick Boseman) his superheroic abilities.

The film implies that the plant’s unusual nature comes from the vibranium deposits buried under Wakanda, but what if it’s from the Soul stone instead? After all, one of its uses in Black Panther is for whoever ingests it to visit the souls of their ancestors, which seems like an appropriate side-effect and reflects one of the Soul stone’s comic-book abilities – opening up a gateway to an idyllic pocket universe.

And maybe, just maybe, the vibranium itself comes from the Soul stone. In the prologue to Black Panther we see the metal falling to Earth and glowing from the centre – so could the soul Stone be encased inside, perhaps also making vibranium as tough as it is?

For now, we’ll have to wait and see what happens, but we’re hopeful that the solution to the Marvel Cinematic Universe’s last big mystery might be within our grasp. Though what that means for the health of Wakanda (and its crucial vibranium products) after Infinity War, we couldn’t say.

Avengers: Infinity War will be released in UK cinemas on the 27th April