It's been four years since Thor: The Dark World hit theaters. And the Thor trilogy ends with next month's Thor: Ragnarok. A mystery surrounding one of the characters has finally been solved. Kind of. At the end of Thor: The Dark World, we learn that Loki has assumed the identity of his father, Odin (Anthony Hopkins), ruling Asgard on his own. So, where did Lady Sif go? Warning, there will be SPOILERS for Thor: Ragnarok below, so read on at your own risk.

When Thor: Ragnarok started production back in November 2016, Marvel confirmed several returning cast members, such as Idris Elba (Heimdall) and Anthony Hopkins (Odin), alongside Chris Hemsworth as Thor and Tom Hiddleston as Loki. Many fans were surprised, though, that Jaimie Alexander wasn't confirmed to return as Lady Sif, although there had been several rumors that she was returning, which turned out to be false. Unfortunately for Lady Sif fans, you won't be seeing her in Thor: Ragnarok, and during a recent interview, Marvel Studios president Kevin Feige offered a theory as to what may have happened to her, which ties into Loki impersonating his father Odin.

"It's been in the works for many years, right, since we finished Dark World. What has Loki been doing on that throne in guise of Odin? And we always liked the idea that he was doing a good job! He was doing a good, but shortsighted job. The trains were running on time, but he wasn't paying attention to anything else going on in the universe or in the realms. So that was always one idea. And the idea that he would have to get rid of Heimdall, because Heimdall can see everything. That was an idea, and probably the Warriors Three, to discount them... which is probably an answer to a question I've been asked a few times today: Sif was probably banished. She's off somewhere."

While that explains her absence as far as the story is concerned, it's also likely that she couldn't return for logistical reasons as well. The actress currently stars on the hit NBC series Blindspot, and with Thor: Ragnarok starting production in early July, when most fall TV shows start filming their seasons, it's possible that the schedules overlapped too much and she couldn't make it work. There had been reports that Lady Sif would return, and there was even more speculation that her Lady Sif character will return in August, where a promo for AMC's Talking With Chris Hardwick specifically stated that, "Jaimie Alexander from Thor: Ragnarok is talking with Chris Hardwick Sunday night at 11."

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While Lady Sif seems to be still alive in the Marvel Cinematic Universe, that certainly means that this character could return at some point, perhaps in either Avengers: Infinity War or in the currently-untitled Avengers 4, which is shooting now and will continue filming for the rest of this year, with filming likely spilling over into 2018 as well. Since Marvel has still not released a full character list for either Avengers: Infinity War or Avengers 4, there is no way of knowing for sure whether or not Lady Sif will be appearing in either of those movies, aside from the actress popping up in set photos as filming continues. Unfortunately, Kevin Feige doesn't reveal anything further about Sif in his interview with Cinema Blend, but hopefully we'll find out more soon.