Chris Hemsworth and Mark Ruffalo will be appearing in Thor: Ragnarok, but what about Stellan Skarsgard?
It turns out that's still up in the air, as the actor told Digital Spy that he's not sure what's happening with his character Erik Selvig yet.
"They have an option on me," he said. "I don't know what decisions they'll make, but they have an option on me for the next Thor movie."
The Marvel Cinematic Universe has become a global phenomenon, but what's it like to be a part of that world?
Referring to a moment in Thor: The Dark World, Skarsgard said: "When you're standing naked at Stonehenge, you don't think of the enormousness of the universe you're in. You think of the cold and how small your dick will be, if Disney is allowed to show it!
"But I worked with very good directors and I've had a lot of fun doing it.
"Of course, doing Selvig is not as challenging as it is to do River, but it doesn't mean it's boring. I'm having a lot of fun doing it."
And on one of his big scenes being cut from Avengers: Age of Ultron, he revealed: "I wasn't supposed to be in [the movie] in the first place.
"Then they called me and they'd written a couple of scenes, and I went and did them and you did not know if they were going to end up in the film or not.
"I want them to make as good a film as possible. I don't care if I'm in it or not."
River is released on DVD and Blu-ray on Monday, November 23 through Arrow Films.
