She is a stalwart at the annual fashion bash.
And Sienna Miller once again pulled out all of the style stops, as she attended the Met Gala at the at the Metropolitan Museum of Art in New York on Monday night.
The actress, 41, oozed 1920s style as she channelled a Flapper in a backless black feathered dress with a thigh slit up the leg, revealing her toned pins.
Sienna teamed the look with a diamond headpiece and a pair of pearl drop earrings, while her blonde locks were worn slicked back into a neat bun.
The British star further accessorised with a pair of fingerless PVC gloves and a pair of bejewelled silver heeled sandals.
Sensational: Sienna Miller once again pulled out all of the style stops, as she attended the Met Gala at the at the Metropolitan Museum of Art in New York on Monday night
Stunning: The actress, 41, oozed 1920s style as she channelled a Flapper in a backless black feathered dress with a thigh slit up the leg, revealing her toned pins
The Anatomy of a Scandal star completed the glamorous look with heavy grey eye make-up and a slick of matte pink lipstick, with her makeup and skincare done by Wendy Rowe using Charlotte Tilbury Beauty.
During the evening, Sienna, who is dating model Oli Green, 25, shunned her beau in favour of attending the party with her longtime pal Emily Blunt.
Emily and Sienna first attended the Met Gala together in 2019, and then again 2021.
The best pals posed for a series of adorable animated snaps together before heading inside to the exclusive bash.
Sienna was later pictured attending an after party at the Mark Hotel in the city, sporting the same outfit that she wore on the red carpet.
The biggest night in fashion took with a slew of the industry's most notable stars walking the red carpet to showcase their glamorous and daring looks.
The 2023 Met Gala returned to the Metropolitan Museum of Art in New York City, with everyone from Kim Kardashian to Paris Hilton attending the fundraising event.
Since 1948, stars have ascended the majestic staircase into a very exclusive party where no selfies are allowed.
In keeping with tradition, the event was held on the first Monday of May and the annual extravaganza kicked off at 6:30PM EST on May 1.
The ball's theme was Karl Lagerfeld: A Line of Beauty. The late German designer was Chanel's long-time creative director. He passed at age 85 in 2019.
Glam: Sienna teamed the look with a diamond headpiece and a pair of pearl drop earrings, while her blonde locks were worn slicked back into a neat bun
Cute! During the evening, Sienna, who is dating model Oli Green, 25, shunned her beau in favour of attending the party with her longtime pal Emily Blunt
Date: Emily and Sienna first attended the Met Gala together in 2019, and then again 2021
His beloved cat, Choupette, was even invited to the festivities.
The decision to honor Karl sparked controversy given the many offensive remarks he has made over the years, from slamming the #MeToo movement to opposing same-sex marriage.
'I'm against it for a very simple reason: In the 60s they all said we had the right to the difference. And now, suddenly, they want a bourgeois life,' he told Vice of same-sex marriage.
'It's difficult to imagine—one of the papas at work and the other at home with the baby. How would that be for the baby? I don't know. I see more lesbians married with babies than I see boys married with babies. And I also believe more in the relationship between mother and child than in that between father and child.'
While he ultimately showed his support for same-sex marriage at his spring 2013 Chanel haute couture show, he still said he was 'less keen' on same-sex couples adopting children, according to AP.
Along with the Vogue editor-in-chief, Anna Wintour, who runs and hosts the annual event, the 2023 MET Gala was co-hosted by Penelope Cruz, Dua Lipa, Michaela Coel and also Roger Federer.
While the show may be known for its glitzy and over-the-top red carpet - with details of what occurs inside often remaining mysterious - at its heart, it is a fundraising event for the Metropolitan Museum of Art's Costume Institute.
Last year, the 2022 MET Gala alone raised a grand total of $17.4 million, reported Billboard.
This year the price of admission was raised from $30,000 to $50,000, according to Page Six. But even if you have the funds, that doesn't guarantee you entry into the party.
Rolling through: Sienna was later pictured attending an after party at the Mark Hotel in the city, sporting the same outfit that she wore on the red carpet
Every guest has to be invited, and a waiting list exists for the coveted golden ticket.
And status matters, according to The New York Times, meaning the hottest stars are a shoo in for an invite.
Heiress Paris was among the biggest names to attend the event, in what marked her first ever Met Gala.
However it didn't go off without a hitch, as her grand Met Gala entrance was blocked by angry climate change protestors who laid in front of her vehicle.
But the small disruption didn't stop the billionaire from arriving on the red carpet and stunning an off-the-shoulder leather dress.
The best dressed of the night included Met vet Kim, who wowed in an incredible pearl dress, as she seemingly revisiting her Playboy look from 2007 by accident.
Kim wore custom Schiaparelli, covered in 50,000 pearls that were hand-strung and draped onto her body.
The mother of four revealed that she wanted pearls because 'what is more Karl' than 'iconic Chanel pearls,' she said during her interview on Vogue.com's livestream.
Pregnant Rihanna, Gisele and Emily Ratajkowski also honored Karl in their statement gowns as they brought their A-game to the red carpet.
Meanwhile, Blake Lively, a frequent attendee, announced she would not be attending the party this year. 'I will be watching,' she said, according to People.
As for Wintour's role in the bash, Vogue's editor-in-chief organizes the party and oversees the guest list and even the menu.
She has served as the Met Gala's chairwoman since 1994 and continues to serve look after look at every event.
Elegance: Sienna showed off her moon tattoo on her back
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