"But I never wanted to kill the show. I thought we were a natural for the movies, we always thought we were making movies for TV. And we did the first one, it did well. We did the second one and it didn't do as well. And then it seemed like it was done. And then TV just changed itself. Cable started doing the most amazing television and ushered in seasons of six, eight, 10 and12 episodes. Then it became clear that we can do it this way."
The X-Files features on the cover of this week's TimeOut:
The further adventures of FBI agents Fox Mulder and Dana Scully (Gillian Anderson) will take place across six new episodes that will screen from next Thursday on TV2. Duchovny admits his working relationship with Anderson has had its ups and downs.
"You're talking about eight, nine years of working 12 to 14 hours a day with the same person, and on top of that we went from complete obscurity as actors and people to worldwide stardom.
"I think we both went somewhat crazy. It's such a big change in one's life and such a big strain on one's time to make that show, that we went a little nuts. You'd have to. So I think there were times where we were nuts with one another, or she was acting crazy or I was acting crazy or we were both acting crazy. I look back now and go 'Oh, I was a little crazy' and I think she can do the same thing and I think we can both appreciate why the other was crazy, and forgive."
Of the six new episodes, the first and last will concentrate on the show's ongoing UFO conspiracy plotline, while the other four will feature standalone stories.
"Mulder hasn't really changed," says Duchovny. "What's interesting for me as an actor is to be able to go back and play him years later. Gillian and I are different actors at this point. We just got better at what we did over time."
The X-Files shone a light on a type of popular culture that has grown to dominate the mainstream. Did Duchovny see that coming at all?
"I was shocked. Because it's really not my thing. I was shocked that people were interested in aliens. I was shocked that people liked science fiction. I was shocked every step of the way. So imagine my shock when I saw [what happened]. They were like 'Go to Comic-Con'. I said 'Never! Never will I go to something like Comic-Con! Are you crazy? I'm so uninterested in all of that.' Now, I gotta go to Comic-Con."
"So I've been behind the curve, blind to that movement, and I'm happy to be part of it. Happy to have a job and happy to work and happy to try to be vital in a culture.
"But again, I think I'm playing my own little game within it. For me the challenges are to act like a human being and try to be real and do all these things that Gillian and I liked to do. And Chris and the writers take care of the stuff that makes it pop culture-worthy."
The conspiracy-laden world view presented by The X-Files can't help but also seem a little prescient in the post-Edward Snowden era.
"My own personal view on conspiracies is: people can't keep secrets. I've never known anybody, one person, one f***ing person, to keep a secret. I find it hard to believe that they're keeping the aliens from us. Because it's pretty juicy. That was my problem with JFK. If there was a conspiracy to kill the president, somebody talks. There's too many people. There's too many secrets to keep. It's not human nature. I don't believe in it.
"Does the government keep secrets? Yeah, sure. Are some of them worse than others? Sure yeah. So I think that's where I find the reality of it."
Duchovny's highest-profile project since The X-Files was Californication, where he played a caddish lothario who couldn't be further from Fox Mulder.
"I wanted to do a comedy. I wasn't seeing movie script comedies that I could do. I saw Californication kind of as this comedy from like the 70s, more suited to me than maybe the antic comedy that maybe Ben Stiller or Jim Carrey were doing at the time.
"Which is hard for me to do. I'm not suited to that so much. Temperamentally. Physically. Any way really. So I was kinda despairing that there was no comedy for me to do, but I felt funny. And then that came along."
The new episodes of The X-Files feature some notable guest stars, including Community's Joel McHale and Kiwi comedic actor Rhys Darby. "He's great in the episode," says Duchovny of Pakuranga's favourite son. "Rhys was great. I'm a big fan of Flight of the Conchords. So for me that was fun to be able to work with him. I love the roll call." Duchovny pauses. Then raises his forefinger in an appropriately officious manner.
"Roll call!"
Who: David Duchovny
What: The X-Files
Where and when: TV2, Thursday January 28, 8.30pm