Some of the Marvel Cinematic Universe's most beloved films and villains are those that have appeared in the latest wave of movies. Thor: Ragnarok, for example, found a lot of success with critics and fans alike, especially following the rather disappointing Thor: The Dark World. The movie's popularity is due in no small part to Thor's villainous sister, Hela. Although she apparently died at the end of Thor: Ragnarok, a new fan theory suggests Hela might return in some capacity for Avengers: Endgame.

The theory, which comes from user MelodicBeginning on Reddit, poses that there might be some evidence to suggest that Cate Blanchett will return as Hela in Endgame. The theory builds off the reappearance of Red Skull in Avengers: Infinity War, Marvel Studios' tendency to keep certain actors and roles under wraps and a previous Reddit post. The post points out an image of a statue in Durham Cathedral, which will likely appear in Endgame, and compares it to an image of Blanchett being interviewed near such a statue. The initial photo was supposedly taken during filming for Avengers: Infinity War, but the location didn't make it into the film's final cut.

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"This location was used in Thor's vision scene which was induced by Wanda in Age of Ultron," the post reads. "This location is theorized by many to be Valhalla (the land of the fallen from asgard who are considered honorable) as it features a vision of Heimdall saying 'We are all dead', these scenes were likely intended as a setup to the Thanos Duology, the Infinity Stones scene with Thanos ended up paying off in Infinity War. So this scene may be referring to the fact half of Asgard is dead and now in Valhalla after Thanos killed half of Asgard."

The post then speculates that, following her apparent death at the end of Thor: Ragnarok, Hela went to, well, Hel, which will be the location for which Durham Cathedral stands in.

This is definitely just a theory and so should be taken with a grain of salt. Even the poster is aware that Hela may not appear in Endgame. However,  making use of Thor's vision in Age of Ultron would certainly help bring the MCU full circle as it prepares to move on to Phase Four and beyond.

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Avengers: Endgame will arrive on April 26, 2019. Directed by Joe and Anthony Russo, the film stars Robert Downey Jr., Josh Brolin, Mark Ruffalo, Tom Hiddleston, Chris Evans, Chris Hemsworth, Jeremy Renner, Chris Pratt, Elizabeth Olsen, Chadwick Boseman, Sebastian Stan, Benedict Cumberbatch, Paul Bettany, Samuel L. Jackson, Cobie Smulders, Benedict Wong, Zoe Saldana, Karen Gillan, Vin Diesel, Dave Bautista, Pom Klementieff, Scarlett Johansson, Tom Holland and Anthony Mackie.