Chris Hemsworth is fighting ... someone. We're not sure if we're allowed to say who just yet (but, he's fighting someone you would probably not expect Thor to be fighting), but Hemsworth describes it succinctly as “a big fight scene.” And, he's not kidding.

We're on the set of Avengers: Age of Ultron, inside the new Avengers Tower; formerly Stark Tower and now converted to a de facto headquarters for the Earth’s mightiest heroes. It’s all very sleek and shiny and pretty much exactly what you'd expect from a place Tony Stark calls home. Except now, it's a complete disaster. There's broken glass scattered across the floor. Furniture is destroyed. There are giant gashes in the wall. There's a production assistant dramatically swinging a giant cape around (the actors film their fight scenes without the cape, and the cape is added later in post-production).

“This is their first meeting really and, as you can see, it's conflicted,” Hemsworth deadpans.

It's a big day on the Age of Ultron set. I literally said, “whoaaa” when I saw what was being filmed. Some day soon we'll be able to tell you more about what exactly was going on and who Thor was throwing down with.

Until then, here's what Hemsworth was allowed to talk about, including some very interesting details on how Asgard fits into Avengers 2.

Can you talk a little about your reaction when you first got the script?

It was awesome. I mean, coming off of Thor 2 and Avengers, you know, I couldn't wait to read this. I just loved how it upped it in a way that wasn't just bigger and flashier. I mean, everything had been amplified, but in an intelligent way. All the stories are relevant to what's going on in the world, as far as the exponential growth of technology and artificial intelligence and the questions of good versus bad and the A.I. world. They're obviously heavily influenced by that tone and that debate. He's managed to bring all of the Avengers back in and give them a relevant reason to be there and justified sort of conflict. I mean, it's a tricky balance. I'm glad I'm not the one writing the thing and having to pull that off.

How does Thor tie into the larger “Age of Ultron” in this film?

We pick up with Thor having stayed on Earth from Thor 2, so he's here, he's part of the team. This is his home for the moment. The initial kind of threat, the attack from Ultron, is personal because it's at all the Avengers, and Thor then begins to see a bigger sort of picture here about what this threat could be potentially, and begins to kind of tie-in all of our films. It’s hard to say too much without talking about what I can’t talk about but as I said, it's a personal loss from the get-go because it’s at him, but I guess he sees a bigger picture.

What’s something Thor gets to do in this film that he hasn't done before in the other films?

He’s loosened up a bit. I think we lost some of the humor and the naïveté, that sort of fish out of water quality of Thor from the first film into the second one. There were things I loved about what we did in the second one too, tonally, but that sense of fun… I would have liked it to be there a bit more, and Joss I think felt the same way.  So there's more humor in Thor or at least because he's been on earth, he's a little more accessible now.  He's off Asgard now so he doesn't have to be as regal and kingly as he is in that world, which is nice. I enjoy that more. It's sort of a box, which is tough to step out of on Asgard. You know, that stuff just looks out of place whereas here, he can have a gag with the guys and he can throw away lines and be a party scene with them in civilian clothes, which is nice.

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The last Thor was very fish out of water a little bit. How acclimated is Thor, I mean does he go to the movies with his girlfriend?

Yeah, I mean you know, I walked on set and we had a scene that was sort of the Avengers, it's a party scene and I was in a nice coat and jeans and the guys just kept joking, about when did Thor go shopping? Did he buy this online or did Jane do it, or did he actually go shopping? You don't see him go shopping but the question’s raised, because he's not dressed in his Asgardian attire. Yeah, I think he's more human in the film, definitely.

Do we see him going to the movies with Natalie [Portman]?

Yeah, I pitched that! I did. But no.

We see that you’re in your classic armor, so does Thor get a costume change in this one?

It's been tweaked. It's been more comfortable. Each time you get a little more comfortable, a little more movement in it. I don't think there's any huge changes to it. I loved where it was in the second one. I think we sort of landed on something because it was a bit more kind of streamlined and functional. It's pretty similar.

It's just an onslaught and it doesn't stop. It's sort of an open floodgate and what it could also set in motion is an even bigger threat.

Thor and Hulk had some awesome scenes in the first movie.  Do we get more of that in the sequel, more of you and Hulk?

We're not as conflicted as we were before I think. He tags off with someone else though.  I think we sort of changed it up there, and he has a pretty solid battle with Iron Man in this one, which is cool. It's a lengthy fight scene of destruction.

Adding new faces both against you and on your side, how has that been, especially with guys like Paul Bettany and James Spader on set?

It's awesome, you know? It just shakes things, because — and I find this in my individual films — you get comfortable. We get into a rhythm or a routine and you think you know it.  Until that's challenged you kind of go “Oh, yeah, that's right. There is another option here” and you can keep changing it and mixing it up. That’s what this new cast does is all of a sudden, it breaks the familiar rhythm that we may have and makes it a bit more unpredictable. We're lucky. To come back and actually want to come back and work with these guys and hang out again and pick up where we left off is a pretty special thing, and it's been great. I do love working on this set.

Can you talk about what brings Thor back to the team this time?

Yeah, I mean it was just giving him a solid reason to be there, you know? I think all of us. It seems like a pretty simple demand but yeah, it would be easy to fall into, “Oh, they're all just there because we're all contracted and look cool if we’re standing in the same room.” (laughs) I mean it was there from the beginning, too, but I just sort of kept saying to Joss, “Okay, what do I bring to the table though, besides kind of Thor being one of his foot soldiers and the muscle in a bunch of fight scenes. What is his knowledge he can bring to it?”  And trying to incorporate that he's from another world because you forget that, too. All of a sudden you're standing there in these conversations and you go, “Well hang on, he’s from another planet, you know? What's his thousands of years of existence? What information can that bring?” And so he calls upon some of Asgardian knowledge in this and is able to go into, say, another realm to pull out something that's hugely useful. Some information that certainly benefits where they’re at at that point.

Do you know how you’d want the character to end?

No, I mean I have asked the question but the truth is no one has the answer yet. We don't know how it's going to end and the biggest concern is this one here, more so than two or three films in time. I'm sure they are coming up with ideas and attempting to kind of have some arrangement that five or six years down the track they go, “Okay, this is where we're heading” but they don’t tell us until the day before usually. Like this fight scene we learned this morning.

How much connection does Thor still have with Asgard, or is he divorced from it completely?

Up until the third act or sort of halfway through, he begins to have suspicions about what's going on here or what this bigger picture is here and who's involved. He starts to think something’s not right here. This is all a little too convenient why this has happened, which certainly points his focus back there.

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Does anything really impress Thor in terms of what’s thrown his way?

I think he openly admits, “I don't think we’re going to win this one.” Yeah, the threat is so great that I think all of them are sort of scratching their heads going, “Is this it?” rather than, “Okay, we have to kill this many things.” It's just an onslaught and it doesn't stop.  It's sort of an open floodgate and what it could also set in motion is an even bigger threat. I think that's what's Thor’s kind of stuck on or where his attention certainly is, an even bigger picture of Thor being from Asgard. He can just say, “Hang on, there's a whole universe here which is signaling something else.”

Someone mentioned Scarlet Witch bringing out the inner demon for each character. Can you talk about what that is for Thor and does that eventually turn them against each other?

It's more kind of within their individual selves rather than the team so much. I think they'll begin to have sort of their fears held up in front of them, and for Thor, I think it's a corruption of power. With all of them having this much power and trying to have the understanding that we're in this sort of endless battle here and when this is going to end and how does it end? That scene is actually being rewritten at the moment, if you want to talk to Joss about it, so it's hard to even say what it will be in Thor’s dream sequence but it kicks in motion his movement. That's where he really starts to kind of move through the story. Once that dream occurs he goes, “Oh, I can see what's coming and my fear could be true” so yeah, it’s a ticking clock.

Each time we see Thor his power and abilities keep getting amped up. Are we going to see that in a new display or more powerful or more a more trained version of Thor?

Yeah, I mean in this fight you see it's hand-to-hand combat because it's someone of his equal strength or moreso than him, so he can afford to do that. Whereas with the people who were far less capable than him and not as strong, I said, “You know, let's make sure he's picking up cars and throwing them and ripping things in half and spending a bit more time up in the air and using the elements as opposed to being stuck kind of in a hand-to-hand sort of fist fight with the bad guys.” So yeah, I think it keeps getting kind of amped up and then the stunts become more elaborate. We see him fly a bit more.

Read even more from the Avengers 2 set in our interviews with Joss Whedon, Robert Downey, Jr. and Mark Ruffalo.

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