While Marvel and DC movies may have grabbed the biggest Hollywood spotlight, countless more graphic novels and comic books are turned into feature films all the time. Just look at the work of Scottish comic book writer Mark Millar—the man behind Marvel's Civil War—who has had his creator-owned properties Wanted and Kick-Ass turned into theatrical smashes, and, most recently, Kingsman: The Secret Service, which is out today.

But even though Hollywood has come knocking, comics remain Millar's top priority. Millar's newest venture is Chrononauts (out March 18 via Image Comics), a time travel epic about two scientists (and best friends) who are accidently swept up in the timestream and catapulted across continents and centuries. "I love the idea of exploring time in the same way that space has been explored in stories the past—the idea of America planting a flag in the timestream in the same way they planted a flag on the moon seems really exciting to me," Millar says.

The book is a collaboration with artist Sean Murphy, whose recent work ranges from the undersea horror-adventure The Wake (with Scott Snyder), to his story about a Christ clone called Punk Rock Jesus. "I would have drawn anything [Mark] gave me, of course," says Murphy, whose work has become some of the most in-demand in the industry. "But he happened to pick something that was up my alley—kind of going back to the buddy movies that you saw in the '80s and '90s." 

We spoke with Millar and Murphy about the new book, why time travel has limitless potential, and what it's like to see your own creations turn up at Halloween parties. 

I love the idea of the infinite scope of all space and time. You can set a story anywhere! That's kind of a writer's dream, isn't it?

So, why do a time travel story?
Millar: Time travel is one of those things, like super-speed or flight, that everyone gets as a story function, but there's not really been much in the way of comic books with time travel. In cinema, there's Back to the Future and a lot of things, and we've seen it on TV shows. I love time travel stories, but I haven't really written any.

I thought it'd be pretty cool to do a comic book of time travel. I love the idea of the infinite scope of all space and time. You can set a story anywhere! That's kind of a writer's dream, isn't it? If you're writing Batman, those stories have to be set right now in Gotham City. Whereas if you're doing a story where people can hop around the time stream, as a writer, you've got limitless scope. You're only limited by your imagination.

How did you two decide to work together on this book? 
Murphy: [Millar] offered this project to me two years ago, but I was in the middle of Punk Rock Jesus. It was one of those offers that really hurt. I knew it would mean a lot of sales, a great story—most of his stuff gets turned into movies and whatnot. I was really glad when he came back to me a year later and we were able to move things around and make it work.

Millar: I'd just admired Sean for a long time. It's like actors and directors—you can admire someone's work from afar and just drop them a line and say, "I think we should do something together." You just wait for the right project. There's a lot of things Sean loves doing. He loves cars; he's obsessed with cars. Every time he gets a royalty check, he just imagines what car or what vehicle he's going to buy with that cash. He sees everything in terms of vehicles. This project had tons of vehicles in it and had lots of period pieces—it had all the things he loved drawing. He loves doing historical research, he loves action, and he loves car chases. I've got this guy for one hundred pages, I'm going to give him the best time.

One thing that struck me about the first issue of Chrononauts is that it's really funny. It seems to have a lighter tone than some of the more recent books you both have done separately.
Millar: I shift gears every now and then. When I was starting out in American comics I was doing children's stuff. I was doing the junior Superman title that was aimed at the animated series audience, and I loved it. I couldn't wait to switch on my computer in the morning! But a lot of the stuff I did beyond that was really dark. Kick-Ass was funny, but it was also very dark. I love doing that too. I think I just shift with how I'm feeling myself. If I fancy doing something light, I'll just write it. I don't ever calculatedly think, "Is there an audience for that?" It's one of the nice things about being a writer that's different from a lot of other jobs. We're quite spoiled, and we just write about what we want to write about.

I don't ever calculatedly think, "Is there an audience for that?" It's one of the nice things about being a writer that's different from a lot of other jobs. 

Murphy: It was cool to do a book that's not quite so serious as most mainstream comics and have a lot of fun. They way he wrote the scripts is very open. I like to inject my sense of humor in there when I can. It's been a really great collaboration working with him.

Millar: There's a bit of a Spielbergian, Amblin kind of feel to the stuff I'm writing right now. I think Chrononauts is a real extension of that. It's funny, because I see it in general pop culture too. I don't know if it's just what people want right now? Guardians of the Galaxy hit such a perfect nerve. It was beautiful. I remember going to see Guardians and just feeling fantastic and wanting to see it again. Whenever times are tough, when there's endless war and economic bad news and terrorism, it's nice to get perked up. Chrononauts is in that vein.  

Can you guys talk a little about your collaborative process? How do you work together to turn the script into the final product?
Murphy: With Scott Snyder, he gave me loose dialogue, and if I wanted to add a panel or take away a panel he was fine with it. He'd project his writing around the art, so it was more of a back-and-forth process. With Mark, what I have is the absolute final dialogue. He doesn't want me changing things around—in a way, it's a bit easier, but it's also nice to have the final dialogue so I know which character is saying what. With other writers, they'll change the final dialogue, so this sarcastic look I'll give a character won't quite fit the new copy. Mark sticks with four or five panels a page, so there's a lot of space, which is nice. There's a lot of panoramic shots and he's really into two page spreads.  

Millar: Sean's funny in that I've watched some of the greatest artists alive—guys like John Romita, Frank Quitely, Bryan Hitch—but every time Sean sends me a page it surprises me. Something amazing like 16th century Samarkand where you have a thousand Mongo warriors attacking an American car, that's amazing to see as a double-page spread. It's spectacular. But he can just as easily make people sitting having a chat at a desk incredibly exciting. Every page is a delight. I always embarrass him with this, but every time he sends me a page I send it to everyone I know who works in the industry. I copy him in and say, "Look how awesome this guy is!" I totally mean it, but I think he's mortified by it.

Every generation has to create that generation's heroes. 

How do you approach your creator-owned work vs. doing a book with one of the big two? 
Millar: I didn't get into the business to do creator-owned, strangely enough. I was lured into comics by the fact that I wanted to play with the toys I grew up with. That was my ultimate ambition. Creator-owned is kind of stretching muscles I never knew I had. But, although I had no interest in it at all growing up, I have actually found I prefer it.

I think one of the reasons is that you're adding something to the pop culture mix. If Stan Lee had just written for DC comics and had never created Marvel, we would never have had any of those characters. Every generation has to create that generation's heroes. That's my plan now. For the next five or ten years I just want to build on this universe of characters that I've been building.

Murphy: I like taking on classics if editorial lets me do my thing. If they're nitpicking about what I can or can't get away with that kind of kills it for me. So I tend to go for creator-owned books and new characters just because it's safer. But when you're dealing with a corporation that's owned these characters since the '50s, they have a right to be protective. It's nice to see how high-quality of a comic you can produce without a big corporation helping out. At DC I had editors and assistant editors and a PR person. I understand why companies have operate that way, but if you have five people who know what they're doing, you don't need any of that stuff. 

Speaking of DC, Sean, do you have a favorite classic character you've drawn over the years? 
Batman is obvious, but I'm trying to think of a more interesting answer than that. I think Constantine was a big one for me. I didn't know a lot about the character. I didn't know he had to have the same coat and tie, so I gave him a leather jacket and some other stuff. At first I got a lot of people who were not fans of that at all. But after a few years of that book getting around, people started coming up to and saying, "I can't read any other Hellblazer but yours because the Constantine in my head should have that tie, or that jacket, or that kind of face." It's interesting that people came around to it. The only reason I got away with that is because the book as on the back burner and nobody was really checking in on me [laughs]. 

It's fabulously fun and great to see it on the big screen, but it's really different from creating your own thing.

Mark, what has it been like seeing your creations gain so much popularity outside of the comic book world?  
A couple of years back I saw two girls dressed as Hit-Girl on Halloween. They were maybe twenty years old. They were just on the street by my house going to a party. And then I saw on someone's Facebook page a guy dressed as Kick-Ass. It was a weird thing! It's so odd that something I enjoy doing is just out there in the world. It was a real Being John Malkovich kind of moment—seeing something that was just in your imagination in the real world. When Bryan Hitch and I did the Ultimates we put S.H.I.E.L.D. in charge of The Avengers. Brian's drawing of Nick Fury became Sam Jackson. It's fabulously fun and great to see it on the big screen, but it's really different from creating your own thing. The difference between seeing Wanted or Kick-Ass or Kingsman and seeing your influence on a Marvel movie is incomparable. 

Before you go, Mark, I have to ask what era in time you'd personally go to visit that's in Chrononauts?
: Well there's a scene in Chrononauts where we have the birth of Christ. We play it for laughs—they don't have a present for the kid, but everyone else is handing stuff over. They're going to give him a gold cross that one of them has, but then they realize it's going to freak the kid out because it's the cross he's going to get crucified on. It'd be fun to go back and see something like that. Or it'd be interesting to go back to the 12th century or the 5th century.

But there's something so interesting about what's going on right now. Even if there was a Marty McFly and you only went back thirty years—pre-Internet and pre-cell phones—I think we'd be bored shitless in about three days. I think I couldn't stand to even live in 1990 now, because I'm so used to everything at my fingertips. If I could time travel I'd only dip into the 15th century for a day. After that I'd need to check Twitter. 

Nathan Reese is a contributing writer at Complex. He tweets here