Warning: This article contains spoilers for Thor: Ragnarok and Avengers: Infinity War.
Avengers: Infinity War kicked off with a couple of brutal deaths, as Thanos put an end to the trickster Loki.
Some Marvel fans believe (or are desperately hoping) that the fan-favourite villain/ally will be resurrected in next year's sequel – fuelled by reports that actor Tom Hiddleston has definitely been on set filming.
There's now a fresh fan theory going around about how Thor's brother will be brought back to life... and it includes a helping hand from Death.
Thor: Ragnarok introduced Thor and Loki's sister Hela, the goddess of death played by Cate Blanchett.
Hela seemingly perished at the end of that movie, as the fire demon Surtur destroyed Asgard. But we didn't see her body – and this fan theory is based on the possibility that she survived the attack.
The Reddit user sharing the theory goes on to say that they reckon Thor will find Hela – as well as Valkyrie (Tessa Thompson) and Rocket Raccoon (Bradley Cooper) – and they will go to the same cave that Thor was seen visiting with Erik Selvig in Avengers: Age of Ultron.
"...to use it in some way to allow Thor to travel to Hel and confront Hela who is trapped or residing down there once more, after her defeat in Thor: Ragnarok, to help him bring their brother Loki back from the dead," the post states.
Of course, Loki wasn't the only casualty in Infinity War, what with Thanos finger-snapping half of the world's population out of existence.
Avengers 4 will be released in the UK on April 26, 2019, and in the US on May 3, 2019.
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