Undercover didn't have a Paris show this season. Instead, Jun Takahashi took two models into a forest outside Tokyo in subzero temperatures and photographed them on a silver "runway" consisting of a few Mylar survival blankets ($1.60 apiece) laid end to end. The point—which became clear in a showroom in Paris, where Takahashi talked editors through racks of the clothes—is that the girls weren't cold. The clothes Takahashi designed this time around were a development of the super-technological collection he did for Winter 2007. "I took a break from showing so I could go back and work on it more," he said.

Close-up, the outerwear, in particular, is an amazingly instructive lesson in the possibilities of modern functional design. Takahashi hybridizes biker jackets, puffers, parkas, regular tailoring, and knits to produce lightweight jackets and coats, which are lined with membranes and microcapsules developed for NASA. Some of them absorb body heat indoors and then release it when the wearer steps out into colder conditions. Others will block biting windchill, even though they're ostensibly as flimsy as blazers.

What's cool is that the content is invisible to the naked eye. Takahashi's shapes run the gamut from dégradé-shaded down jackets to tuxedo coats with knit sleeves and rabbit cuffs to techno-satin evening parkas photo-printed with jewelry. Top-grade style desirability and high-spec functionality are built into every piece in equal measure. It's extremely rare that any fashion designer is smart enough to take time to devote to research and development—the onward pressure of having to show every six months actively militates against it. But here, Undercover has produced a range that harnesses modern technology in ways that make dressing for winter an effortless pleasure.