Avengers 2’ director is reassembling almost his entire cast for two weeks in January to film reshoots for ‘Age of Ultron’ and this, in and of itself, is not particularly interesting. It used to be that reshoots were indicative of a larger problem—”the movie isn’t working, so we need to go back and fix it”—but that simply isn’t the case anymore. Every big-budget blockbuster budgets time and money for reshoots into the original production schedule these days. But, what’s interesting in the case of ‘Avengers 2' isn’t that they’re filming something, it’s what they’re filming and who is involved.

The Daily Mail is reporting that Robert Downey Jr., Chris Hemsworth, Mark Ruffalo, Jeremy Renner, Paul Bettany, Scarlett Johansson and Chris Evans will return to Pinewood Studios in London next month to film some additional sequences. They’re the Avengers, so that’s not so weird. A little more interesting is that they’ll be joined by Tom Hiddleston. We’d previously been tipped to Hiddleston’s involvement in ‘Avengers 2' by Idris Elba, who blew Marvel’s surprise in an interview last month. At the time, it seemed liked Hiddleston and Elba made brief appearances in a vision shown to Thor by Scarlet Witch. But, with Hiddleston returning, it’s possible that he plays a slightly different role in the film than just a mere dream sequence.

Here’s one theory floated by Badass Digest that includes some major spoilers, so we’ll issue a warning up front.

The original script calls for the Avengers to be left divided following the events in ‘Age of Ultron’ with Captain America heading up a new team made up of newer, upcoming superheroes (think Vision, Captain Marvel, possibly Black Panther). According to their sources, this scene was not shot during the original production, in part because some of those cameo roles hadn’t yet been cast. We do know that Chadwick Boseman has been cast as Black Panther, so perhaps the reason for the reshoots was to allow time for contracts to be signed for actors who would eventually become a part of the larger Marvel Cinematic Universe.

We can’t imagine Loki being a part of this—as popular as he is in the Marvel films, we can’t imagine them making him a formal “hero” in these movies—but, maybe he’s of some assistance to our heroes, specifically Thor, in the film. There have been rumors that Thor finds himself banished back to Asgard somehow, and he comes looking to Loki and Heimdall for assistance in getting back to Earth. (Thor’s absence also paves the way for Captain America to payoff that moment glimpsed in the extended trailer, by actually lifting, and using, Mjolnir.)

‘Avengers 2' opens in theaters on May 1, 2015.

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