Talk about moving out of your comfort zone. For his stage debut, David Duchovny chose Neil LaBute’s “The Break of Noon” — which features the former FBI Special Agent Fox Mulder in every scene of its intermissionless run. “It’s an hour and 35 minutes of me, pretty much,” Duchovny tells The Post. “Nobody can stand much more than that.”

The boyish-looking 50-year-old grew up in Manhattan. He graduated from Princeton University and was well on his way to a doctorate in English lit from Yale when he started acting. After “The X-Files” ended its run, he went on to several films and “Californication,” in which he plays a sexually obsessed novelist. He won a Golden Globe for it in 2008 — the same year he announced that he’d checked himself into rehab for sex addiction. He didn’t want to talk about that.

Happily, there was plenty else to discuss, particularly “The Break of Noon,” opening Nov. 22 at off-Broadway’s Lucille Lortel Theater, in which Duchovny stars as the sole survivor of a gone-postal-style office massacre. And then there’s his move, with actress wife Téa Leoni and their two children, to New York City — and moving on, in general.

What drew you to such a demanding piece, and in such a small theater?

I’m living here and wanted to take advantage of what New York has to offer that I don’t get to do anywhere else. I told my agents I was open to doing a play, which was crazy, because I’d never done one. Then Neil’s play came along. When I read the first 10 pages and it was all that damn monologue, I was like, “What the hell!” But then I thought, “Well, it’s interesting and it came my way, so let’s do this one.” It’s a different kind of a piece — different for Neil, different for me, challenging for all of us. I don’t care how many people see it. I just want to have the experience.

How best to describe your character, John Smith?

I kind of see him as an Everyman — not quite like Job, because Job was a better man. I think the idea was that Job was so good, God and Satan made a wager over whether they could make him disbelieve by putting him through hell. John Smith is more of a flawed Everyman. He’s got a bad temper, he’s been unfaithful to his wife with her own cousin and he has a secret he tells us at the end. The rest of the play is this guy trying to figure out what he’s supposed to do with that experience — how he’s supposed to live his life and spread the word. But because he’s so flawed, the audience rightfully goes back and forth on whether this guy is full of s - - - or not.

At one point, John confesses he’s ashamed of things he’s done: “I did a lot of porn.” Any resonance there for you?

I think we all fall in our own ways. Some are bigger than others, some are more public than others, but I think that’s what makes us human, rather than getting stuck. I think at some point in your life, if you’re paying attention, then you start to look back a little and say, “Well, I can’t change the past, but I can change my relation to it.” I think when a man starts to grow up and take responsibility, there’s a certain kind of sombreness that leads to a certain kind of lightness, which is what [LaBute’s] talking about in this play.

Is it hard, separating your roles from your life? And did “Californication” have anything to do with your splitting, however briefly, from Téa?

Oh no. It had nothing to do with that. I don’t have any problem separating roles from life. I think I’m attracted to roles for reasons I learn after I take them. You have an idea but then it becomes something else. My jobs don’t have anything to do with my personal life, and I’d be an ass if I blamed it on anything else but myself.

What does marriage mean to you?

I think [marriage] is a living, breathing thing — it’s organic. It’s two people in that dance, and you’ve got to take care of it. That’s my two cents.

What brought you and your family back to New York?

It was really kind of an experiment. We loved LA, at least I did, but we were a little leery of raising the kids in Malibu, where we lived. Malibu’s a little like a summer place, and we’re both East Coasters and not sure we wanted to raise our kids on the beach. So we thought, let’s get them to New York and see how they do, see if they like it, see if they thrive. It’s still an experiment. We have the luxury of being able to pick up and go if we need to, if we want to.

How old will your kids be before you let them see “Californication”?

I’m always surprised at who seems to watch it. I have people who say “My daughter got me into it,” and I’m like, “Really?” Well, good for us, but I don’t know. I don’t think I’d ever lead [my kids] to it. I imagine they’d be curious at some point and I’m sure they can watch it whether or not I let them — that’s the nature of our age. I’d prefer that they were adults when they saw it, not just because of the subject matter, but because it was their father.

Anything you miss about “The X-Files”?

I think one of the things that attracted me to the John Smith role was the preacher aspect — the voice in the wilderness. I think I still relate to being the voice in the wilderness saying, “Hey guys, this is what’s happening — you’re all wrong.” But for some reason I go toward it. And for some reason, maybe I’m able to pull it off.

Anything you regret about “X-Files”?

Once I said it rained a lot [in Vancouver, where ‘The X Files’ was filmed] on a talk show, and it was blown out of proportion. I wish that didn’t exist because I love that town, city, whatever it is. That’s one of the places I’d live in. I love it, but I don’t think I’ll ever be able to heal that rift, because the spin got out of my control.

What about you surprises people?

I’m often told that I’m taller than people expect. I’m 6 feet, but apparently people expect me to be about 5-foot-2. I don’t know why. It’s a conundrum to me. Maybe somebody who reads this can figure it out.