Profligacy has never been Giorgio Armani's calling card, but today he took rigorous discipline to an extreme with a collection based almost entirely on gray flannel. On paper, it scarcely sounded like the most promising proposition. Is there any fabric more dully corporate? So how on earth did Armani alchemize flannel into clothes of such serenity and grace?

First, he pushed wool to the limit, offering it in every possible weight, from chunky to gauzy: a substantial cardigan jacket versus an evening dress that hugged the body like silk jersey. Then Armani added a splash of lime. That was the perverse stroke of genius that elevated this collection. Green, fashion's least favorite color, in one of its most polarizing manifestations. Except that it worked. That was basically because Armani covered the spectrum of grays and greens, finding unlikely but seductive compatibilities that blurred any distinctions. A knit coat, for instance, that ombré-d its way from dove gray to the vaguest suggestion of green. And a strapless gown that latticed charcoal and pistachio together. When they were layered, green made an eerie underpinning for loosely woven mohair tops.

The designer dubbed his collection Fade to Grey, so it was clear where the emphasis lay. The strongest look in the show was the very first: a single-lapelled jacket curved over cropped, pleated trousers. As corporate outfits go, it was a humdinger. But there was a slash of green stitched where the jacket's buttonhole would be, and that was all you needed to see to know that Armani will always enjoy implying much more than meets the eye.