It's a possibility that Loki might die in Thor The Dark World. I mean Marvel threw out massive spoilers in the recent TV spots. But that doesn't mean he can't come back. In the comics Loki takes possession of Sif’s body, transferring her spirit into that of an elderly woman. It will probably be like that after credits scene from Thor. Where Selvig is being controlled by Loki. In an interview for Thor(2011) Jaimie Alexander was talking about how bad she wanted to play Loki and Tom responded by saying "Well time will come when Loki comes back in the body of Sif". Watch the interview around 4:44 Were they hinting it at the time? Who knows but I'm excited to see what happens.
Thor(2011) Interview with Jaimie Alexander and Tom Hiddleston
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