It's hard not to feel a degree of trepidation before meeting Karin Dreijer Andersson. That's not just down to the contents of her solo album, recorded under the name Fever Ray, or the extraordinary live shows with which she has promoted it – although it has to be said, neither help much. The Fever Ray album may be one of the year's best, an incredible electronic meditation on sleepless new-motherhood. But the kind of adjectives it inspired – brooding, bleak, claustrophobic, creepy, forbidding – don't suggest that the woman behind it, her voice masked by electronic effects, is going to be a barrel of laughs. And the band's live shows – designed by her long-term collaborator, visual artist Andreas Nilsson – may well be some of the most disturbing gigs in recent memory. Venues were completely filled with dry ice, through which you could vaguely make out eerie figures on the stage: a deeply sinister clown, someone dressed as a kind of insect.
But even if you've never seen the shows, or heard a note of Fever Ray's music – or indeed the equally acclaimed, dark and forbidding electronica Dreijer Andersson makes with her brother Olaf under the name the Knife – you could feel wary of interviewing her, based on her previous encounters with the press. The Knife barely talk to journalists at all: much to the chagrin of the Swedish music industry, they also declined to turn up to their homeland's equivalent of the Grammys when their 2007 album Silent Shout won seven awards, sending instead a series of abstract videos.
By comparison, Dreijer Andersson has been on a promotional blitz for the Fever Ray album. But despite the interviews, she has managed to maintain an impermeable aura of mystique. She won't discuss her personal life, claiming that to do so would distract from the music she makes: "I just think that if you create good music, as art it has its own value, and I don't think so much it has to do with the person behind it." And what little she does say tends to the oblique: "My music is a lot of everything."
The already trepidatious journalist is unlikely to be much reassured by Dreijer Andersson arriving in an office in central Stockholm in full Fever Ray get-up: her face painted deathly white, with black lines bisecting her cheeks, her already white-blonde hair augmented with long, straight extensions. She is dressed in a kind of black cowl. In fairness, she's breaking for lunch in the middle of a photoshoot; nevertheless, it's a deeply discombobulating experience watching someone cheerfully demolish a takeaway falafel and discuss the latest US imports on Swedish TV while looking like something that might loom out of a television set in a Japanese horror film.
If she's not quite as austere as some interviews suggest, it's still apparent that you're in the company of a woman who seldom regards meeting the press as the highlight of her day. "Would I like to just make music and not promote it at all? Like, not do interviews?" she ponders aloud. There's a pause; there's often a pause when Dreijer Andersson answers questions, which some interviewers have taken to mean she doesn't much care for what is being asked, but seems more likely to suggest she's just searching for the right words in a second language. Then she finds them. "Yes," she says flatly.
Perhaps because of her reticence, journalists have a tendency to leap on what scraps of biographical information she lets slip and imbue them with vast significance. (When she suggested that her family were "outsiders" in the small town outside of Gothenburg where she grew up, because "we didn't play tennis", one writer suggested that here might lie the key to the sense of isolation that permeates Fever Ray's sound.) However, it's difficult to see how this afternoon's revelation – that she and her husband, a computer programmer, are fans of American muscle cars and intend to spend next summer racing them – corresponds to anything on the album.
For her part, she seems perplexed by the idea of people wanting to know about the artist behind the work. No, she says, she's not at all interested in the lives of people who make music she likes (an eclectic list that takes in Cyndi Lauper, Twisted Sister, Kiss and the soundtrack to Miami Vice – or at least, as she underlines with the certainty of the committed fan, the soundtrack to the first series of Miami Vice, "when there was a lot of very nice electronic music and not so much dialogue"). "I've read almost no books about artists. I'm just interested in the performance part of it. Sometimes I'd like to know how female artists combine their family and their work, but that is more practical advice. I'm not interested in what they had for breakfast."
Then again, Dreijer Andersson seems perplexed by a lot of things you might consider straightforward. For years, she was rigorously opposed to the idea of playing live: "It was very provocative for Olaf and me, when everybody was saying, you have to play live or else you're not a band, blah blah blah. You start to think, why is this so important? I think it's very strange that people who are musicians and composers … I don't think it has anything to do with performing."
She eventually relented – the Knife played a handful of live shows, albeit concealed behind screens, while Fever Ray have thus far clocked up "about 50 performances" – but still has an idiosyncratic approach to performing, which extends to fantasising about not turning up at all. "I think it's very interesting to play with the idea of au-then-ti-ci-ty," she says, carefully. "With the Knife and Fever Ray, I could send some other people out there instead of me and nobody would see any difference. And that's very funny."
She also seems surprised that people find her live show disturbing. "Maybe. I don't know if that's the right word. It shouldn't be a relaxed thing. You should be awake." Her daughters, aged six and three, apparently love it. "My kids are not afraid of it at all. They like painting their faces and dressing up with us. I mean, if you bring them along at the early stage, they know it's face paint, they can paint themselves. When we're about to have a show, all the band are painting themselves and dressing up, it's a joyful experience."
Nor do her band object to taking the stage dressed as clowns and insects. "I told them at a very early stage, if you want to come along with this, you will wear costumes. They really enjoy it." She laughs. "I don't see how they can continue with their other bands after this."
But they'll have to: after a final show in London in December, she plans to retire the Fever Ray project. There are no plans for a follow-up album. Indeed, beyond racing muscle cars and releasing an album of the opera about Darwin for which she and Olaf recently wrote the music (despite never having been to an opera), her plans are as vague as some have found her interview technique. "I don't know what will happen. I will probably start to work with Olaf again. That will take ages, to make an album. But for Fever Ray, for a very long time, it's the last." And with that, she heads off, as mysterious as ever.