Almost every actor who signs on for a major role in a Marvel Studios movie is required to sign a long-term, multi-picture deal. There are exceptions, of course, like Robert Redford, who signed on to appear in only Captain America: The Winter Soldier, but by and large, most actors are locked in for a number of movies. During a recent interview with Den of Geek, Stellan Skarsgård revealed that he signed a five-picture deal with Marvel, and with only one movie left, it might not be the one you'd expect. Here's what he had to say below.

"I have a five-film deal with them, and they still have one option. Thor 3 is not on my slate, but maybe the next Avengers."

Stellan Skarsgard has previously appeared in Thor, Marvel's The Avengers, Thor: The Dark World and last summer's Avengers: Age of Ultron. Production on Thor: Ragnarok is slated to begin this summer, so it's always possible that he could be brought on at the last minute. Then again, it would also make sense if his character Erik Selvig didn't appear in Thor 3.

Back in December, Marvel Studios president Kevin Feige revealed that Thor: Ragnarok will be set largely in the "cosmos," with "very little" of the story taking place on Earth. This could also mean that other Earth-bound characters like Jane Foster (Natalie Portman) and her friend Darcy (Kat Dennings) may have very limited roles, or perhaps they may not appear at all. However, there is one exciting casting addition that has already been confirmed, Mark Ruffalo's Hulk.

Both Hulk and Thor are reportedly set to go on a "cosmic road trip" together, although there isn't much else we know about the story thus far. There have been rumors that the primary villain is Hela, rumored to be played by Cate Blanchett, who teams up Tom Hiddleston and manages to destroy Thor's hammer Mjolnir and banish him from Asgard. Thor is sent to an unnamed planet full of gladiators, where he has to battle his way to the top and fight the planet's champion, Hulk. Of course, none of these details have been confirmed, but they do fall in line with Kevin Feige's comments about most of the movie set in the cosmos.

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As of now, only Chris Hemsworth, Tom Hiddleston and Mark Ruffalo have been confirmed for Thor: Ragnarok, which starts filming this summer under the direction of Taika Waititi. How do you think Stellan Skarsgård's Erik Selvig will fit into the plot of Avengers: Infinity War? Let us know what you think, and stay tuned for more details.