"We kindly request that you refrain from using flash photography," a voice announced over the loudspeaker before the start of Alexander Wang's show. "That includes cell phones." What a bit of wishful thinking that was. Mere seconds after the overheads dimmed toward the end of the show and the black lights switched on to reveal that the models' white clothes glowed an electric shade of yellow, Twitterers took to their iPhones to share their pictures. Wang is just about as It as you can get in New York fashion at the moment, and he delivered on his reputation, sending out a focused Spring collection that put his strong, singular vision on display.

"After last season's austerity," he explained, "I wanted to pull garments apart, experiment with volumes." Wang's is a precise kind of deconstruction. The clothes were all right angles—no asymmetries here—and the scalpel-sharp slices that separated the graphic panels of everything from a clinical white cotton shirtdress to a sand-dune-colored leather jacket were hand-tacked like sutures. As the show progressed, the splices became cutouts in wavy zebra stripes. The experiment reached its culmination in a series of sexy dresses that seemed to float on the body thanks to the invisible fish-line embroidery holding them together. The designer called the effect Tron-like. Fun fact: The first fishing line they tried melted under the heat of the irons used to press the samples, so team Wang had to devise a new one of their own.

Function often suffers when designers put so much emphasis on form, but that wasn't an issue here. Wang smartly stuck close to traditional American sportswear design. Spongy leather T-shirt dresses were modeled after baseball uniforms. Liberty Ross, a catwalker whose star appears to be on the rise after her husband's cheating scandal with Kristen Stewart, modeled a simple windbreaker. The black-light moment will be what people talk about and remember, but even without it, this was a powerful performance.