Jonny Johansson of Acne, the Swedish fashion phenomenon, isn't one of those guys who goes about his business like a big shot. "I'm from reindeer country," he likes to tell people. But he's infiltrated the international denim, T-shirt, and well-priced separates markets with such indie integrity that all kinds of cool people want to be associated with the brand. Like, for starters, Alber Elbaz, who buddied up to the Swede to make Lanvin's hit jeans collection. It was a big stride, nonetheless, for Johansson to pitch up in London and show his line outside Stockholm for the first time. In typical fashion, he lured the curious to the Sir John Soane's Museum, an obscure and marvelous cabinet of ancient and architectural artifacts that many hometowners have never heard of.

What Johansson presented was a far cry from jeanswear basics. "It started when I was sitting in the Café de Flore in Paris and thinking what to do," he said. "I looked over, saw an old guy, maybe in his seventies, hanging out, and his hands were covered in rings. So I started drawing." That image, linked with an inspiration about the kind of girls who populate the Berlin art scene, gave rise to a collection that ran from well-cut tailoring (overcoats and seventies high-waisted pantsuits) to plastic jeans to chunky gold and diamond jewelry made in collaboration with the venerated German artist-goldsmith Michael Zobel. Huge cuffs, rings big enough to occupy two fingers, and saucer or box-shaped pins—all set with rough diamonds, Tahitian pearls, emeralds, seashells, or rough-hewn slabs of semiprecious stones—drew the most attention, and surprise. Delving into precious jewelry might seem reckless in a stalled economy, but Johansson promises he's only following the instincts that have driven him to success since he started in 1993. Acne, after all, is an acronym for Ambition to Create Novel Expressions. He and his team don't play by conventional rules. And as he pointed out, the much-trusted jeans and T-shirts are constantly available online, anyway.