Clark Gregg discusses playing S.H.I.E.L.D.'s Agent Coulson in Marvel's The Avengers, due in theaters May 4

Back in 2008, when Iron Man was unleashed in theaters, Clark Gregg's Agent Coulson character seemed to be a fun but fairly minor character that we probably wouldn't see again. Then again, nobody really knew, at the time, that the movie was the first cinematic piece which lead into Marvel's The Avengers, which arrives in theaters May 4. Clark Gregg popped up in Iron Man 2 and Thor, and his role in Marvel's The Avengers is actually one of great importance, which came as an awesome surprise to me, and the actor himself. I recently had a chance to sit down with this fantastic actor to speak about Agent Coulson and much more. Here's what he had to say.

One of the things I was really impressed with is how many balls (director) Joss Whedon kept in the air, so to speak. Were you worried at all about how much or how little Coulson may be involved, with such a huge cast in place?

Clark Gregg: Yeah, absolutely. As someone who is a fan of this world and of these movies, I was worried that it wasn't possible to pull it off, to keep all those balls, not only in the air, but also evolving towards something, in a way that also worked as its own story. And, on top of that, the idea that this many characters were in it, and Coulson would do anything but pass through in the background in a helicarrier or something, seemed improbable. I got the script, and all of those things were accomplished, and Coulson was a big part of it, it was kind of a red-letter day in our house.

I read that (executive producer) Louis D'Esposito said Coulson wasn't always planned as going through this whole series. When you went out for the first Iron Man, was it discussed at all back then, that you would be on for this whole run?

Clark Gregg: No, not at all. Marvel was clear where they wanted to get to, and they knew some of the steps and who some of the characters would be, but I don't think they knew how they were going to get there. That was just the sense I got. When I showed up for Iron Man, it was just a very small character who wasn't in the comics. To their credit, something about it worked. It was a way to bring S.H.I.E.L.D. into the mix, and they just kept adding stuff and putting him in other movies. It's something they adopted, and I was just really lucky to be in the right place at the right time, and delivering something that seemed to work.

I loved the little bromance we get here between Coulson and Captain America. It's cool because he's such a straight-laced, by-the-book guy in the other movies, and you see this whole other side of him here.

Clark Gregg: That's the funny thing about doing this guy. I never would have thought of that. The minute I read it, I thought, this is really going to redefine this guy, to a certain extent. And, at the same time, it feels absolutely correct. Every time I would get a new script, I would go, 'Oh, that's who he is.' It never seemed like it broke the core, to what I was connected to, it just seemed like it rounded it out. Joss so clearly got Coulson and Tony Stark and all these other voices. It just made sense.

Yeah. The more I thought about it, the more it really made sense, that he would study Cap.

Clark Gregg: Also, in the world of this, Cap is a real guy, who then had comic books written about him, which Coulson read as a kid, and, I think, inspired him to the point where he went through the grueling steps necessary to end up in S.H.I.E.L.D., and then suddenly the guy is there 50 years later. I'm not surprised, there was such a crush.

Can you give us a sense of life on the set with Joss? I loved the humor in this. We have seen humor in the other movies, but it seems to be at a whole other level in The Avengers. Was the set as light just as light and amazing as one would expect?

Clark Gregg: It wasn't just all bouncing around, happy and goofy, because it just was too vast of a task. But, the script really worked, for the most part, and everybody knew it. At the same time, it created a formidable task, just to try to deliver what was on there. Because that was there, I felt people were professional enough, and knew this is kind of like The Avengers. It's life imitating art. We have a real serious job here, and we have to show up and do it. We can't do it by being all teeth-grinding and intense, we have to relax, and, support each other, and really get there.

I was really blown away by the visuals, some of these big, sweeping scenes. Can you talk about the amount of green-screen that you had on the set?

Clark Gregg: There were enough amazing sets. Most of my stuff, like the Helicarrier, they were just so real. They did a lot of it for you, all the stuff in the containment chamber. A lot of the stuff in New York, they really had a city there. I guess the combat stuff required a lot more of the green screen, and my combat was all pretty real and close-quarters.

I actually met you last year on the set of The To-Do List.

Clark Gregg: Oh yeah. I remember that day.

I remember you said you had just came off The Avengers, and then you were going back. Was the whole shoot like that for you? Were you in and out the whole time?

Clark Gregg: Yeah. I was able to go back home a lot. If I had three or four days off, I would just go home to be with my family. It really took the sting out of it, for me, because I was closer than the people who lived in New York. Then, other times, I'd be there for two weeks, and go out dancing with some Avengers. That was pretty fun.

I can just imagine a club with all these Avengers.

Clark Gregg: I suggest that, actually, you probably can't, because I could not believe what I was seeing at the clubs.

(Laughs) I see that you also reunited for another project with Joss, Much Ado About Nothing.

Clark Gregg: Yeah, we did it already. Joss is so crazy, he shot a little indie version of (William) Shakespeare's Much Ado About Nothing at his house, during his week off, because that's his idea of a good time. Luckily, we had enough fun on The Avengers, that he called me up and asked me to do it. I'm really glad I did, because it was an amazing experience.

There was that teaser poster released awhile back, and I remember thinking, 'Wait a minute. When did he shoot this?'

Clark Gregg: No one ever told me not to tweet about it, or email anybody about it. I just didn't, because I was busy just trying to learn all the lines very quickly. Then, afterwards, they put that out, and the internet just went nuts. People really want to see anything Joss does.

I remember I was just trying to do the math. It was like, 'Well, he wrapped (The Avengers) on this day. Did he really shoot this in that many days?'

Clark Gregg: I know, it doesn't make any sense.

I've been a big fan of your work for awhile now, and I really loved Choke.

Clark Gregg: Oh, thank you.

I was wondering if there was more writing or directing in your future?

Clark Gregg: Yeah. I've written a movie I really love, this thing called Trust Me, which I've been trying to get the financing for and start shooting for a couple of months. I'm hoping it's going to happen this spring.

Do you have cast locked in?

Clark Gregg: I have a couple of people signed up, but I'm not going to say anything yet.

I'm a huge fan of Chuck Palahniuk. I know there are a lot of his books that haven't been adapted yet...

Clark Gregg: I agree, I know. I'd love to do another one of Chuck's.

People thought Fight Club was unadaptable, and then you saw what happened there. It's just his style of writing, and people think that it can't be done. It's obviously been proven wrong, but he has such a unique style.

Clark Gregg: I think it's a really specific kind of dark satire that really freaks people out.

Great. Well, that's all I have. It was great talking to you again.

Clark Gregg: Thank you.

You can watch Clark Gregg as Agent Coulson in Marvel's The Avengers, which hits theaters nationwide May 4.