I Was There: Juiciest Behind-the-Scenes Moments from the Met Gala Red Carpet

The first Monday in May was also a night of firsts for some A-listers.

“We’ve never done this before,” Matt Damon told Yahoo Style on the red carpet at Monday’s Met Ball. His wife, Lucy, sported a gorgeous new ’do and the two matched designers. “She’s wearing Versace. I took about five minutes. She was pretty quick too.”

Versace dressed another Met Ball newbie: Celine Dion.

When it comes to red carpet prep, Mindy Kaling, too, is a quick study, saying it took her about 90 minutes to get ready for her third Met Ball —- this time in a stunning Prabal Gurung number. “Last time I got here about 10 minutes before the evening started. I didn’t get to see the exhibit. Now, I’m excited [to see it].”

Yes, folks, there’s more to this evening than just eye-popping style. Welcome to that annual sartorial showdown known as the Met Ball, which raises funds for the Anna Wintour Costume Center, and this year, celebrates enigmatic and crazy-talented Japanese designer Rei Kawakubo of Comme des Gar?ons.

“We’re all wearing her ideas,” said Pharrell Williams.

No, he didn’t feel any pressure being on the host committee, along with Katy Perry and power couple Gisele Bundchen and Tom Brady.

“It’s great. It may be [high-pressure], but I don’t feel that way. What I feel is lucky and blessed to be able to do it because it’s one of my heroes. Rei Kawakubo is the best of the best,” Williams told Yahoo Style.

The star-studded event featured those who adhered to the theme and went all-out, like Tracee Ellis Ross in Comme de Garcons, and Rihanna, who wore the same designer and shut it down in an ensemble no mere mortal could manage. She did it with aplomb.

Brady took photos of Bundchen on his phone as she posed for photographers. Serena Williams, pregnant with her first child, was looked on adoringly by her fiancé, Alexis Ohanian. “Gorgeous,” he mouthed to onlookers. Indeed.

Perry could barely make it up the stairs in her scarlet Maison Margiela number and headpiece. Kim Kardashian, one of the last to arrive, turned up solo, clad in austere white Vivienne Westwood, with nary a jewel in sight.

And her sister Kendall Jenner showed bum-aplenty in barely there La Perla. And then there’s Jennifer Lopez, who turned up with beau Alex Rodriguez and looked breathtaking in Valentino, or Dakota Johnson, dreamy and romantic in black Gucci — she’ll the new face of the brand’s upcoming fragrance.

The Met Ball is an odd beast, like the Vanity Fair Oscar party, which is wall-to-wall celebrity, minus the faux-relaxed burgers-and-cigarettes vibe. There’s an actual receiving line, with attendees — each hand-selected and approved by Vogue editor in chief Anna Wintour — paying tribute to the year’s hosts and chairs before entering the storied Manhattan venue.

All the major design houses participate, and the clothiers bring celebrities as their dates. Naomi Watts attended with Stella McCartney this year, while Zac Posen went with perennial favorite Katie Holmes.

Jemima Kirke, Lily-Rose Depp and Brie Larson donned Chanel. Bella Hadid rocked Alexander Wang. Halle Berry, who stumbled slightly as she headed up the steep staircase in sky-high heels, was stunning in Versace. Elle Fanning was feminine in sweeping, strapless Miu Miu.

Some used the opportunity to talk about things other than just pretty frocks.

Livia Firth “has never been, and never will be,” a shopaholic. Instead, she’s been using her voice to encourage responsible fashion; at this Met Ball, Bundchen took part in Firth’s Green Carpet Challenge and wore a bespoke Stella McCartney gown that’s in line with Firth’s mission to get repeat use out of clothes and to source them responsibly. “It’s incredible. Tonight I’m wearing pineapple. It’s made out of pineapple leaves,” Firth said of her dress.

Yummy.

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