With Captain Marvel now in theaters, it marks the first time Clark Gregg's Agent Coulson has been on the big screen in the MCU since 2012's The Avengers. Coulson was the glue that helped build the MCU in the first place starting with his appearance in Iron Man 2, and his death in The Avengers was the entire reason the titular team assembled in the first place. While he's been busy reprising his role on ABC's Agents of S.H.I.E.L.D. for the past five seasons, fans are no doubt happy to see him back alongside Samuel L. Jackson's Nick Fury in Captain Marvel—even though they're playing much different versions of their characters.

The origin story Captain Marvel stars Brie Larson as the titular hero, but it takes place in the 1990s and finds Fury and Coulson in the nascent stages of their eventual partnership. To have the actors play versions of themselves that are 20 years younger, Marvel Studios turned to its cutting-edge de-aging technology that was previously used on actors like Michael Douglas and Kurt Russell, and the results are stunning.

With Captain Marvel now in theaters, I recently got the chance to talk to Gregg about his work in the film. He discussed how he first found out he'd be in the movie, how the de-aging technology worked on set, and how much room for improv there was. He also talked about the future of Agents of S.H.I.E.L.D. and the show's limitations with regards to the MCU, and how they all thought the show was ending when they were shooting Season 5. Check out the interview below.

Collider: The de-aging technology in this movie is both scary and exciting. Halfway through the movie when I was watching it, I forgot that the technology was in play.

CLARK GREGG: Someone else told me that. I haven't seen the movie, but someone else told me that they were watching it, and they forgot it was young Sam. They just forgot.

It's crazy. What was it like working with this technology?

GREGG: There's not much going on, on the day. You look like yourself with some dots and more hair, both of us. Hilarious thing was his dots were white and my dots were black, which I thought was very like ebony and ivory. Yet, that's it. And we're kind of looking at each other, grizzled veterans that we are, and going, "Oh, shit. We're younger. We're younger. I gotta remember to act that." So sometimes I'd kind of feel like I let a little old, grizzled, traumatized, beat up Phil Coulson slip into it, and I'd be like, "Wait, wait, whoa, whoa. Let me start over." Because this is a guy who isn't even really sure what exactly he signed up for yet. He just knows that this guy Fury is cool, and he wants to learn from him I feel like it's the moment when he's realizing, "oh this is exactly where I'm supposed to be. This is my destiny, is to be part of this, and to work with this guy." That's the process of this movie, which I think is a cool moment in anyone's life.

A lot of fans have been waiting for you to return to the MCU movies. What's your reaction when you get the phone call that you're going to come back, and you're going to be much younger, and it's a prequel, and it's in the '90s.

GREGG: Cool. '90s are cool. "You're going to be in a Blockbuster. There's going to be cool '90s jams throughout the movie, Boden and Fleck, who did one of my favorite indies of all time, Half Nelson, are directing it, and P.S., your favorite young actor, Brie Larson, is going to play Captain Marvel, and she's going to have the cool costume, and P.S...You're going to see the helmet with the Mohawk. Please. Oh, by the way, Ben Mendelsohn, one of your other favorites, and Jude Law are all going to be there." It was a very short conversation. I was very psyched about it.

How early on are you told about the project in terms of when you're going to be filming? I would imagine scheduling is a thing, so how early did you know this thing was moving forward in relation to and then you were filming it?

GREGG: Not too long. I remember I got a call from [producer] Lou D'Esposito saying, "Are you interested in this?" As I said, very brief phone call, and then I feel like a week later tops, I was at the Black Panther premiere, because I took my family. I wanted them to see that. They just freaked out, and loved it, and then we went to the party afterwards, and I saw Kevin [Feige], who was really funny and said, "We were starting to read actors. We were putting together a list for young Nick and young Phil." I was like, "I hope I'm going to like who's on that list." And then he said, "But then we talked, and we said, oh, well. They both look okay. They both look pretty good, actually, and we've got that de-aging thing. We did it to Stark, we did it to Kurt Russell, so we'll spend a little more money." I was a little worried how much money they would have to spend to make me look like 1990s me, but it was thrilling. It was thrilling to me.

Kevin said to me that one of the reasons they could pull this movie off is because the two of you basically haven't aged.

GREGG: On the inside. On the inside, we're just beat up. [laughs] I won't speak for Sam. They said, "We'll pay for a trainer." I was like, "Look, pal. There is no trainer that can take me back to 1995." And they said, "Well the rest of that our digital guys..." I remember one day, I had been taking jiu-jitsu, which I do sometimes, and I'm sure I walked into an elbow, and I had a big shiner, and I walked into the makeup trailer all nervous, like you're trained to be, going, "Look, I'm really sorry about this. Can you cover this up?" They just said, "Ha! Pal, it's the least thing we're going to do to you is get rid of that shiner. Remember your dots?" I was like, "Oh, yeah. Good point."

Compared to some of the other MCU movies you've been a part of, was there more adjustments on this one? Was it more sticking to the script?

GREGG: When Joss is directing his own script, there's a version of a lockdown where it's just really...I don't know. That said, I remember Joss really coming up with some great stuff on the fly on the day, maybe other people, but not that often. This felt like that, but also there were places where there was a real flexibility, an indie filmmaker's kind of flexibility to making the scene work in this space and based on the stuff we've done before. Then as Marvel shrewdly always does, four, five months later, you're back doing a couple new scenes, a couple new pieces that really flesh out what's going on, and that part of it's always fun.

I definitely want to touch on Agents of S.H.I.E.L.D. I have really enjoyed the last few seasons. Talk a little bit about what's coming up this upcoming season, and the fact that you are directing.

GREGG: I directed the first one. We had this very unusual experience in that we...we're very tight. We've been through a lot together. We've really been on this journey, and we're a family. There we were at the end of season five doing an episode called "The End," and really no word on any pickups, so the feeling was this probably was the end, and Phil Coulson had burned through whatever brought him back in The T.A.H.I.T.I. project by being Ghost Rider, and it looked like he was done. So there were really emotional goodbyes that were all very real, because we felt like we were saying goodbye to each other.

Then God knows, a month later, we get a call saying, "No, they just picked us up for 13 episodes, six and seven." We were thrilled because 13 episodes feels like the right number to make a show these days that's trying to compete with all the other 10, 12, 13 episode cable things and streaming things. But no one wanted to buy back cheaply the fact that he was terminal, and all that emotional stuff, and so they asked me to direct the first one, which was really nice. As time went on, they started to talk about what they were thinking about exploring, and the idea that Coulson could be gone, and in a space-time rupture that's going on, these aliens—if that's what they are, they don't even know—who show up, one of them could be ... What do they call them?

Shapeshifter?

GREGG: Not a doppelganger, but like...Oh my god. I can't remember. Like Alt Phil. A different person. It's different than that, what they came up with. It's what I admire about the writers on our show. So much of the Marvel Universe is off limits, because it might be in Phase Two, it might be in Phase Three. What can you have? You can have LMDs. Go do that. Or you can have this transdimensional doorway. You can have this alt-version of people, but you can't have this, and they've really managed to kind of just let it crossover when it crosses over, it's connected when it's connected, but they take that stuff and create their own world. To kind of get to play another character within that world, and the story that they...the question, really, that they came up with for the beginning about who the hell this guy is, and the position that puts the people who've just lost someone who looks like this, I thought was really, once again, I went, "well, okay, I'm excited about that. I'm back."

I want to ask you about directing. After all these years, you know how many VFX shots you get in an episode, you know the infrastructure of how to make one of these. So talk a little bit about trying to put your mark on this episode within the constraints of when you have X number of VFX shots, X number of days to make the show, you have only so much time to set up a camera rig to do a shot.

GREGG: Yeah. It's a really good question, especially the first episode I directed in season 5, I felt like there's going to be so much attention paid to this. If I finally do it, I just got make it be like mine. But I really just felt like the script is the script, and all I can really try to do is do a great job on that episode, and whatever is Clarkian about it is just going to come out or not. You know what I mean? It couldn't really be my focus. They're so different, the two episodes they gave me to do, that it was really an honor to be given 6x01, because as you probably know, they tear it all down and start over every season. The director of the first episode is really introducing the new world. We had two of them, some people in space and some people on Earth, and really setting the tone. The fact that I was also introducing a new version of myself was kind of a weird, twisted bonus.