PARIS — It all started with a pearl, perhaps the pink, pear-shaped one that Karl Lagerfeld wore as a tie pin when he took his bow at the end of an exceptional Chanel show. Or maybe it was his poetic vision of silvery mother-of-pearl found among the sea creatures and ocean fronds that formed the show’s all-white set. For Chanel’s spring-summer 2012 collection, Mr. Lagerfeld plumbed the ocean depths and rose to fashion heights. He changed the Coco look from safe to sporty and introduced modern fabrics, like an eerie transparent plastic jacket cascading with stones and worn casually over a swimsuit. But, above all, the collection was indisputably and irrefutably Chanel, almost every piece turning on the pearl that is one of the Coco icons.
“I love the sea — it’s very mysterious, and fish scales seem so modern; there was everything but mermaids!” Mr. Lagerfeld said backstage. What could have been a kitschy romp on the ocean floor was instead a magical show that drew energy from the sporty attitude of the models walking in silver shoes with conch-shaped heels. By replacing the signature Chanel chains with the equally iconic pearls, Mr. Lagerfeld lightened up the day wear. The show started with the newest iteration of the Chanel suit, stripped of chains and gilding, the jacket cropped short and belted at the waist with pearls. Later, the show moved into evening wear: fitted jackets worn over skirts frothing with feather-light fabric. The lacy and mesh dresses that followed were so airy they could have dressed sprites on a sandy beach rather than sophisticates at a cocktail party. This tour de force highlighted the power and energy of a brand that Mr. Lagerfeld seems to have right under his skin. For Chanel – and for fashion – the designer is a pearl beyond price.