She's very beautiful. But she looks like she might kill you," says Gareth Pugh of model Alla Kostromichova, the lovely - if admittedly somewhat intimidating - face of his new limited-edition line of makeup and accessories, designed in collaboration with M.A.C. And that just about sums up not only the designer's aesthetic more broadly, but also this latest venture.

On a table in front of us, all packaged in fiercely heavyweight, high-shine geometric black, is a duo-chromatic nail polish that flashes from emerald to amethyst; a powder designed to suit all skin colours and render the complexion entirely - almost a touch morbidly? - matt; and lip gloss that is relatively discreet when worn alone but high-impact when layered over dark and distressed shades of lipstick. Then there are probably the most enormous false eyelashes the world has ever seen - they're called Flight Lashes, presumably because should they catch the breeze their wearer might inadvertently take to the skies in them, which would be good.

"I got the biggest ones M.A.C does and chopped them up, basically," Pugh laughs. "When you put them on top and bottom they work really well. They look like horse blinkers." Speaking more generally, he says of the origins of the collection in question: "M.A.C asked me to send them things that I like - colours and textures.

I went through my studio and I never throw anything away so I've got all this stuff." It almost goes without saying that said "stuff" is more than averagely interesting. "There's a butterfly ring, which is how we came up with the iridescent thing. There was a haematite rock that I'd picked up in Evolution in New York. I can't resist that place. It's full of dead things and crystals. I sent M.A.C the feathered head-dresses from my spring/summer 2010 show - light grey feathers, that's how we came up with that colour. It's all come from the same place so it works as a collection, I think. It tells a story."

And that story brings together what Pugh describes as "two opposing elements that can be merged and mixed. You've got a very dark, quite full-on element, and then there's an ethereal, silvery grey side to the collection." A promotional film has been shot with Kostromichova playing two different characters. "It's a bit like a fight. There's friction there," Pugh says. Directed by Ruth Hogben, styled by Katie Shillingford, with makeup directed by Val Garland for M.A.C and music by Matthew Stone, the end result, which will be screened in-store alongside the product, is a group effort between people who have worked together often. And, like all the best link-ups, the relationship between Pugh and M.A.C has also developed over an extended period of time.

He has long been supported by the cosmetics company, with independent make-up artist Alex Box and the M.A.C Pro team working on the makeup for his biannual ready-to-wear shows. M.A.C also shares with the designer a less than conventional approach to physical appearance. It has been associated with everyone from Lady Gaga to Elton John and from Pugh to newly installed fashion diva, Miss Piggy.

"We've known each other for a long time now, M.A.C and me," Pugh says. "I've seen what M.A.C's done in the past and it's been great - very thoughtful and well-presented. The company understands me very well. I don't do a lot of collaborations, especially not with big companies, and I think only a few of those would be willing to commit to this level of investment: custom packaging, a film. It's been done really beautifully and, like I say, M.A.C has done my shows for many years, makeup is important to my shows, I wear makeup and it's kind of let me do what I want."

Pugh (30) has been wearing makeup since he was 8. He grew up in Sunderland, England, and excelled at ballet in particular ("like Billy Elliot"). "You had to wear makeup for the dancing," he says now. "I remember my mum taking me to Boots and buying me blue eyeshadow, white eyeshadow and lots of bronzer." Aged 16 he was forced to choose between a career in dance or fine art and opted for the latter. Following a foundation course at the City of Sunderland College he came to London, completed the BA fashion course at Central Saint Martins in 2003, and immersed himself in club culture, specifically !WOWWOW!, a creative collective located in a huge squat in Peckham where Pugh had his studio.

It wasn't long before the designer was making stage costumes for Kylie Minogue and, soon after that, for Marilyn Manson. Knitting with refuse sacks and making dresses out of balloons; fringing his signature strong shoulderline with cellophane and decorating oversized coats with pin-pricks of electric light, he showed at London Fashion Week as part of the Fashion East initiative to support young talent and then, from the autumn/winter 2005 season onwards, solo and under his own name. In 2006 he received backing from Michelle Lamy, the wife and business partner of designer Rick Owens, and his label is still produced in partnership with her, which facilitates his more recent use of considerably more upscale materials, with production values to match. In 2009, Pugh won the prestigious ANDAM award; he now shows in Paris alongside fashion's big guns, to both critical and commercial acclaim.

If Gareth Pugh, the company, has grown up quickly, from purveyor of theatrical and even art-house indulgence to luxury goods brand with a menswear line, pre-collections, small leather accessories and now makeup, it's worth noting the anarchic spirit that characterised his early work is still very much in evidence. There's never been anything shy and retiring about Pugh's vision of women - or men for that matter. Oh, and he continues to wear makeup to this day. "Everyone has insecurities," he says. "I occasionally have very bad skin and so I got into the habit of wearing makeup to disguise it. Now I don't really leave the house without it, even if I'm just nipping to the shops. To me, it's like putting my shoes on."

M.A.C, similarly, is not a name readily associated with the shrinking violet.

"There's instinctually a synthesis between Gareth Pugh and M.A.C as brands," says James Gager, the cosmetic company's senior vice-president and creative director. "M.AC loves black and Gareth loves black. We love a bit of goth; Gareth, from the beginning, has always loved a bit of goth." More seriously: "The main thing is that Gareth is this young, vital, progressive creative force. I feel that aligning ourselves with someone like that says a lot to both our [makeup] artists and our customers about the vitality of M.A.C as a brand."

For Pugh the experience has been a good one on every level. He holds up for inspection everything from the colours themselves to a black makeup case to contain them. "Look. It's really good," he says. "You've got a place for your lippie and for your shaver in here. My mum and aunties are very excited about their Christmas presents this year.

"I didn't think about this project in terms of expansion. For me, it's never like that. I did it because M.A.C asked me and it's a great thing to do. It is really nice, though, that people who maybe can't afford my clothes can buy this. It's a bit like having a perfume, something that's entry level, a lot more inexpensive but still part of me. It's really satisfying for me to do something beautiful that a lot of people can buy."

- INDEPENDENT

By Susannah Frankel