Mark Fast's challenge for his first stand-alone show at London fashion week was brutally clear: How could he build an entire collection from his particular area of knitwear expertise, which is so defined…no, make that restricted?

His bizarre story line—a utopia destroyed by acid rain—couldn't offer much by way of inspiration, though perhaps Fast took its central notion of destruction and resurrection to heart when he combined his trademark open-stitch knits with sweeping swaths of fringe, thus giving something that is limited by its body-consciousness a whole new movement and openness. The designer's used fringing before, but it had a real allure when it swung in sunset shades off the hem of a fitted web of a dress in a peachy color. Still, it's never going to escape its showgirl associations. In fact, there were moments when Fast even seemed to be playing up that idea, so Vegas-ready were some of his outfits.

As far as the knits themselves went, he was after a new precision—less webby, more geometric—though his lattice of keyholes bared more flesh than ever. Even when he covered up, it was with inserts of see-through plastic (oddly parked at crotch level in one number). A collaboration with Swarovski produced dresses that limned the body with crystals. The showgirl-o-meter remained curiously unmoved by those, perhaps because they were nothing compared to the put-your-eye-out patent bras that accessorized the collection.

So did Mark pass the Fast challenge? The jury might be out for one more season.