Many shows during Mercedes-Benz Fashion Week were light and airy. But two of America's hottest young designers — Alexander Wang and Prabal Gurung — went over to the dark side in dueling un-spring-like collections held in dank warehouses wedged between the West Side Highway and the Hudson River.

Gurung, who normally shows his collection in the window-filled lobby of an ultra-modern building, chose Pier 57, an unairconditioned warehouse with concrete floors and virtually no visible light, to showcase his spring line. I have to admit there was something amusing about watching sweaty fashion editors in designer cocktail dresses tottering in 6-inch stilettos as they made their way to their seats in the nearly dark surroundings, sidestepping pools of water that collected on the hard floor.

Yet the hard-edged space, pumped with fake smoke and thumping music, seemed a fitting location for a collection that was much tougher than anything that Gurung has shown previously.

The designer alternated black and white looks, pitting an embroidered white jacket with a chiffon tail and cropped slacks against a black tailcoat and tunic that, in the Blade Runner surroundings, seemed like a battle between good and evil.

As it progressed, the collection grew softer and more coloful, with floral jackets, dropwaist dresses adorned with feathers and sequins, and an eye-catching red organza blouse — which the program note referred to as a "muscle tee" — over a tank with graphic inserts. The last look, a strapless dropwaist dress with embroidered red feathers, could have come from a classic Bill Blass collection. That seems fitting, because that's the fashion house where Gurung got his start.

Wang, who regularly shows his collection in a similar dark warehouse, Pier 97, in Midtown, has long featured a more urban edge. Hipsters Justin Theroux (the fiance of Jennifer Aniston) and members of the South African hip-hop band Die Antwoord — including Yo-Landi Vi$$er, who wore a white net mask over the bottom half of her face, and Ninja, who shot photographers the bird — added the proper street cred, along with New York Knicks basketball star Tyson Chandler, who wore designer shorts that fell below the knee.

Wang's spring collection was almost exclusively black and white, with a mix of smock-like shirts, leather bibs and dresses with cut-out pieces threaded together to move like an undulating stream when the model walks down the runway. Nearly every look, from pencil skirts to boxy "hockey jersey" dresses, featured geometric pieces in suspended detail. Sweaters were molded to the body in patterns of thick cable knit, and cropped parkas were made of a futuristic-looking rubberized twill.

Their hair parted with a strip of tape down the middle, models wore barely-there makeup and minimalistic gladiator boots to add to the "don't mess with me" attitude.

Liberty Ross, the 33-year-old model and estranged wife of Snow White and the Huntsman director Rupert Sanders, confidently walked the runway in a white poncho and pencil skirt. (Sanders had a brief fling with Twilight star Kristen Stewart, which continues to keep the tabloids in a frenzy.)

Before the show, a voice on the loudspeaker asked the audience to refrain from using flash cameras or cellphones, which seemed like an odd request, because snapping photos and sending them via Twitter or Instagram have become key components in the fashion publicity machine.

But the reason for the request became apparent at the end of the show, when nine models dressed in all-white stood in position while the lights went out, transforming them for a few seconds into neon glow sticks.

It was the first shot of color in the entire show.