LONDON (AP) -- London Fashion Week kicked into high gear Sunday, with a hectic day of shows that culminated in Lady Gaga taking a starring turn on celebrity milliner Philip Treacy's catwalk.
Earlier in the day, punk queen Vivienne Westwood upstaged her own models in a finale that saw her strutting down the runway with a climate change slogan T-shirt.
Fashion doesn't get more theatrical than this.
Day Three of London's twice-a-year style extravaganza was packed with runway previews by some of the capital's most popular designers: Westwood, Paul Smith, Jonathan Saunders, Mary Katrantzou and Alice Temperley.
But Lady Gaga, in a hot pink, floor-length shroud, stole the show when she opened her friend Treacy's Michael Jackson-themed comeback show. Treacy, who has designed fanciful hats for Gaga as well as countless royals and celebrities, has not shown at the fashion week for a decade.
Raising her arms and looking up, the pop icon announced: "Ladies and gentlemen, the greatest milliner in the world: Philip Treacy."
She was joined by fellow celebrities Kim Cattrall, Grace Jones, and Nick Cave in the front row at the show, which featured Jackson's legendary stage costumes paired with Treacy's headgear.
The outfits, which included the original red "Thriller" jacket -- were lent from a collection held by the King of Pop's costume designers. They are set to be auctioned in California in December.
The spectacle topped a long day of shows that featured onetime punk priestess Westwood, who championed her favorite cause - climate change - as she closed her runway preview.
The orange-haired designer used two models to unfurl a banner proclaiming a climate revolution, then strutted down the catwalk herself in a "Climate Revolution" T-shirt, shorts and makeup that looked as if she had a giant black eye.
"I loved it," former model Jo Wood said. "There was so much there that I wanted. And I love Vivienne as a person. She's the one show I won't miss."
Some of Westwood's severe outfits looked like they were from just before the "Mad Men" era, when U.S. first lady Mamie Eisenhower helped set conservative fashion trends.
Some outfits looked silly, others - evoking the Jackie Kennedy era that came a few years later - appeared wonderfully retro and chic.
Did the ensembles work? Westwood, ever the iconoclast, claimed she simply didn't care, insisting she was only interested in using fashion as a way to air her views on the environment.
Westwood wasn't the only person looking to the '50s and '60s for sizzle and spice. Sophia Loren was the inspiration behind Alice Temperley's London catwalk show Sunday, an elegant concoction of '50s full skirts fit for a royal garden party.
Temperley, a favorite of Kate and Pippa Middleton, said she wanted to update the 1950s couture look and make it accessible.
The designer said the conical hats the models wore exemplified the classic couture feel of the spring collection, which was set in a grand chandeliered hall.
"I wanted to create something modern and sleek, something that gives the feeling of the dream of couture," she said of the hats, which were similar to the style worn by Audrey Hepburn in "Breakfast at Tiffany's."
Working from a soft palette dominated by powder blue and ivory, Temperley showed off flirty, tea-length circle skirts and dresses that accentuated a tiny waist. A theme was skirts with semi-sheer horizontal organza stripes, which Temperley said was to show a bit of leg and make the retro look more fun.
Textures were luxurious and soft with lace, silk, brocade and tulle with flower appliques.
Temperley is best known for her romantic evening and bridal gowns, and is launching a more affordable line at British department store John Lewis.
On Friday, Kate Middleton, now known as the Duchess of Cambridge, wore a Temperley ice blue dress with white lace sleeves to a tea party in Malaysia.
Loud clashing colors, full-on sequins, holographic stripes - Jonathan Saunders' catwalk show Sunday had it all. These aren't clothes for the shy woman.
Saunders, who chose to stage his spring collection in the industrial underbelly of the Tate Modern museum, opened with a series of silver and gold separates with a holographic sheen.
Skirts and dresses made of a plastic-like material with large circle discs came next, the discs glimmering like fish scales in the spotlight.
But the star of the show was stripes, stripes and more stripes. There were bright lime trouser suits and dresses in thick horizontal stripes, a black and white dress in a chevron stripe, and dresses with flowing stripes of a clashing color that cleverly followed the bias cut of the garment.
To end, Saunders upped the '70s disco fever feel with a series of fully sequined dresses in bright stripes of color: Black with blue and silver, and black with red and green. On another designer it could have looked tacky, but on Saunders, it somehow all worked.
While other designers work summery watercolor hues and bold prints, Marios Schwab's catwalk show Sunday was a darkly seductive affair of shredded leather, smoldering midnight tones and tribal detailing.
Drawing inspiration from an idea of the Amazon warrior, Schwab opened his show with a series of dresses in sheer layers of black and oxblood, decorated with leather tassels.
These tassels appeared throughout the show - adorning high heels or flat lace-up gladiator sandals, on lapels, in short parallel rows down the bodice, or strategically shielding the body on sheer gowns.
Schwab also created texture with pleating, which was used first on leather dresses in fuchsia and inky blue, then later on chiffon skirts paired with lace tops in the same hue.
Schwab's designs always play on seduction and have a mysterious femme fatale element to them, and his spring collection was no exception. Models' bare bodies were just visible under the layers of light material, and at times high slits on the pleated leather skirts revealed flesh-toned mesh layers beneath.
The final evening pieces - nude or sheer black high-collared column gowns embellished with tassels and beading - were dramatic showstoppers.
The Greco-Austrian designer's show was packed, with front row guests including Japanese Vogue's editor Anna Dello Russo.