As bizarre as much of the new film “Nowhere Inn” is, cowriters and costars St. Vincent — aka Annie Clark — and Carrie Brownstein are on somewhat familiar ground when it comes to playing with rock-star/media archetypes in deadpan fashion. They’d previously had satirical fun with some weirdly comedic short films they made to promote “Masseduction,” St. Vincent’s 2017 album. But “Nowhere Inn,” which premieres Jan. 25 at the Sundance Film Festival (and is also set for South by Southwest), takes these ideas next-level. Brownstein and Clark play heavily fictionalized versions of themselves in a sometimes broadly comedic, sometimes surreal movie that could be described as “Portlandia” meets “Mulholland Drive.”

The longtime friends had actually wrapped up filming on “Nowhere Inn” before they collaborated on record last year, with St. Vincent producing “The Center Won’t Hold,” the latest album by Brownstein’s band, Sleater-Kinney. In real life, they’ve managed to stay friends as well as collaborators — something that doesn’t work out nearly so well for their characters in the movie. Brownstein is seen attempting to direct a documentary about St. Vincent, whom she comes to consider too boring to be a proper film subject. Her attempts to make Clark more interesting on camera have the effect of making St. Vincent turn into a monstrous parody of a narcissistic rock star… and of slowly pushing Brownstein toward madness. Variety caught up with the duo in Los Angeles to discuss this unusual project.

Was there ever any talk of doing a real documentary at some point, before you came up with this fictional twist on one?

Clark: Probably at the end of 2017, I basically begged Carrie to do a tour documentary with me. The initial idea was that it would be a partially straight-ahead tour doc, but there would also be these kind of comedic, weird interstitials that stitched the show footage together. And then the idea went way more involved and way more bonkers and thoughtful.

Brownstein: It started to feel like there was a disconnect, going from Annie’s St. Vincent persona and performances, something that was so heightened and embraced a certain amount of artifice, to these casual sketches. It would be a very jarring viewing experience. Also, I think it’s hard when you already have something like “Spinal Tap”; you never want to do something that’s going to be compared to that. And we were uninterested in sort of commenting on other people’s music documentaries — that wasn’t really panning out. So we thought: Let’s make something that is multi-genre and a little more in this kind of ’70s thriller vein, like “Privilege” or “Performance,” where you’re adhering to a story but also taking the audience on a very unexpected ride in which they just have to buy into the weirdness of what you’re doing.

What would you say this movie’s genres are? It seems kind of like a mixture of show business satire and psychological thriller.

Clark: With just a scotch of horror, I would say.

Brownstein: I was watching a lot of Nicolas Roeg and thinking about the ways that his films have a hybridity to them. … But yeah, it seems like part thriller, part satire — although I don’t think we were quite thinking of it as much as a satire. I guess any time you’re playing a director, there’s something satirical about that.

It’s hard to think of who else that’s prominent in rock ‘n’ roll could have fun with a role like this, playing off having a very dramatic, visually avant grade persona, where some people might feel let down seeing you have a normal real life. As St. Vincent, you’re the exception among contemporary rock stars, in doing something as theatrical as a David Bowie or a Kate Bush. But nowadays, most rockers try to cultivate and flaunt an everyday persona.

Clark: It’s something that Carrie and I have talked about ad nauseam for a lot of years now. Especially with the proliferation of social media where the new currency is relatability, it’s “Let me pull back the curtain, and look, I’m really normal” — normal-slash-aspirational. It makes actually being normal impossible to parse and discern, and it just puts reality in a very strange space.

Dan Doperalski for Variety

Brownstein: And I think one of our explorations was of how what is couched as a real documentary is completely artificial anyway. Most of the time artists are in charge of what’s being filmed and how it’s being edited and how they’re being portrayed. To claim that there’s realness behind it is its own falsehood. So we just decided: Let’s explore those things without actually just following Annie around with a camera. So there’s something very meta about it, I guess.

Clark: It took me a very long time in years of watching documentaries to watch them with any kind of discerning eye. I was like, “Well, this is the truth — it’s a documentary! There’s a slide-y blues guitar score under this! It’s authentic.”

Brownstein: One of our explorations was of how what is couched as a real documentary is completely artificial anyway. Most of the time artists are in charge of what’s being filmed and how they’re being portrayed. … I think this [fictionalization] services Annie’s music more than just a straight-ahead film and puts her squarely in that Bowie category, which has always been a fair comparison.

Did you ever have to pull back to not make it too funny? Imagining watching it with an audience at Sundance, it’s hard to know when or how much people will laugh.

Brownstein: I think our sensibility is just the more real things are, the funnier they are. You can’t play into the humor of a scene.

Clark: I have such a question mark as to how people will respond to it at all.

Brownstein: In a lot of the writing leading up to it, people are just like, “Oh, and St. Vincent has a music documentary at Sundance.” l hope they’re not expecting something straightforward. But I think that surprising people and upending their expectations is something that we’re interested in doing — and I think services Annie’s music more than just a straight-ahead film. I think this puts you, Annie, squarely in sort of that Bowie category, which has always been a fair comparison. I think this is a more interesting way of presenting you filmically than, you know, “St, Vincent: Revealed” or something. … I feel like this is a nice distillation of a lot of things that we’ve talked about as friends and colleagues for years. We were able to, in a narrative context, hash out just some of these heavier conversations, in a way that’s hopefully entertaining and not too didactic.

Clark: Watching it back, it’s like a really sweet distillation of our relationship over the years. I think it’s sort of poignant. Well, I don’t know if that’s for me to say, actually. “It’s poignant!”

Brownstein: Our performances are electrifying? Can I say that? “Electrifying performances, and a poignant, poignant film.” I mean, it bears repeating. We’re gonna do our own pull quotes for this. Can we do that? “Four stars — Annie Clark”?

Although the film gets more and more outlandish, it is surprisingly sweet toward in the end in a few moments where there are flashbacks to the time when your two characters were still friends. For all the meta content, the movie also does a good job of capturing something relatable about how sad it can feel like when power dynamics in a friendship change and people grow apart … even if things don’t usually end up quite as nightmarish as they do in this film.

Brownstein: I think [the flashbacks were] important because you get so far, you could sort of lose sight of like, why does this matter? Why do we even care about this friendship?

Clark: We needed to definitely establish the fact that we were really close and it’s a bad thing that we’re not. [Laughs]

Brownstein: Otherwise it’s just like, who cares, and who are these people?

Clark: That’s the pull quote. “Who cares and who are these people? – Carrie Brownstein.”

What kind of life do you imagine this film having?

Brownstein: I’m excited to surprise people. I don’t think it’s necessarily what either of our fans are expecting, particularly. I think people are just assuming it’s pretty straightforward. Although I think it doesn’t quite exist anymore, my goal would be that midnight-movie feeling of something that’s a cult classic. It would be nice if people twatch it again and circulate it among their friends: “You’ve got to watch this bonkers film.”

Clark: Yeah, I want kids in 20 years to be watching it, like, “Oh, my God, you didn’t see ‘Nowhere Inn’? It’s bananas.”

Brownstein: Yeah. “Bananas” is a good pull quote.