Bum deal? Madonna steals the show with revealing outfit at Met Gala Ball
Madonna left little to the imagination as she arrived at the Met Gala in a lacy black dress exposing her buttocks and barely covering her breasts.
The Queen of Pop, 57, posed on the red carpet in the revealing outfit at one of fashion's biggest events of the year, dubbed the Oscars of the East Coast.
Beyonce also created a stir, attending the New York gala alone in a pink latex gown by Givenchy.
She has faced rumours of marriage problems with her husband Jay Z following the release of her new album Lemonade, which contains lyrics about infidelity.
British actress Emma Watson donned a black and white bustier, trousers and train - and revealed she was actually wearing plastic bottles.
Watson's statement ensemble, created in collaboration with Calvin Klein and Eco Age, was crafted from yarns made from recycled plastic bottles, as well as organic cotton and silk.
She told her 32.8 million Facebook followers: "Plastic is one of the biggest pollutants on the planet. Being able to repurpose this waste and incorporate it into my gown for the âª#MetGalaâ¬ proves the power that creativity, technology and fashion can have by working together."
The event celebrates the Metropolitan Museum of Art's new exhibit, Manus x Machina: Fashion in an Age of Technology, which provided the gala's theme of the convergence of man and machine.
Rapper Kanye West attended in ripped jeans and a sequinned jacket, completing his look with blue contact lenses.
He struck a casual look next to his wife, reality star Kim Kardashian, who wore a floor-length silver gown split to the top of her thigh.
West wrote on Twitter: "thank you Olivier for making 4 dresses for Kim to choose from which we chopped 2 in half. and thank you for turning my personal jean jacket into a couture piece ... We just had fun with the "future" theme !!!"
Idris Elba led the British talent on the red carpet as one of the gala's hosts, and had some fashion tips for men getting ready for the event.
"Take your time," he told reporters. "Make sure your shirt's down and the whites of the cuffs are out."
Also attending - and following Elba's advice - was The Night Manager star Tom Hiddleston, who went for a classic white tie look.
Former One Direction star Zayn Malik arrived wearing armoured sleeves over his suit as he accompanied his girlfriend, model Gigi Hadid, who wore a sequinned dress with a semi-transparent skirt.
The celebrity duo went all out for their red carpet debut as a couple as they co-ordinated their metallic outfits.
Taylor Swift, another of the gala's co-hosts, embraced the event's theme with a short silver-sequinned Louis Vuitton gown with high black gladiator sandals.
Her close friend Lorde arrived on the red carpet sporting a plaster cast on her left arm.
The New Zealand-born pop star wore a tiered tulle dress in pastel colours, with a low-cut bodice. She did not reveal how she had been injured.
Lorde was joined by fellow pop stars Lady Gaga, who wore a ribbed bodysuit from Versace, and Katy Perry, who donned a black velvet Prada gown.
British musician FKA Twigs wore a jewelled headpiece linked to her nose ring as she was joined by her boyfriend, actor Robert Pattinson, who wore a white tuxedo jacket.
Pop star and TV talent show judge Rita Ora took flight on the red carpet in a feathered silver gown.
The dress, with cut-outs across her torso and legs, flared dramatically to form a peacock-style train.
Star Wars actress Lupita Nyong'o turned heads with a towering hairdo, drawing the focus upwards from a sequinned green dress.
Bond star Naomie Harris wore a Burberry dress for the event, bucking the sequin trend in favour of detailed embroidery and heavy fabric, while British supermodel Naomi Campbell wore a black dress with silver beading.
Tickets for the invitation-only event reportedly cost 30,000 dollars each (£20,500) or up to 275,000 dollars (£188,000) for a table, with the money raised going to the museum's costume institute.
Met Gala chairwoman, Vogue's editor-in-chief Anna Wintour, had the final say over the guest list of around 600 people and arrived at the gala with her daughter, Bee Shaffer.