Cartier knows how to throw a party.

That was the general consensus on Friday night, when the French fine jewelry brand took over Milk Studios Los Angeles on Cinco de Mayo for a sprawling bash celebrating the launch of the Panthère de Cartier watch.

“Looks like Boom Boom Room,” remarked a guest walking in with Anna Dello Russo. “Very New York, no? This is how you do it.”

"Golden Hour" noted the invitation, and fittingly, black and gold was the theme with striking, metallic palm trees set against all-black furnishings. After walking down a long hall with draped black walls and deep green carpeting, guests were welcomed into a room overflowing with champagne, featuring a large raw bar of oysters, crab claws, and caviar. The room then led into a much larger space showcasing a stage and dance floor, where the night’s anticipated performer, Alicia Keys, got everyone on their feet with hits like “Fallin’” and "Empire State of Mind".

“I like this basement party vibe,” Keys told the crowd. Lion Babe’s Jillian Hervey and Lucas Goodman had just stepped off stage, and Mark Ronson’s DJ set would follow. “You ever been to a basement party? Let’s vibe a little bit right now.”

“I never leave my house, and I don’t go out very often, but when I saw Alicia Keys on the invitation, I really wanted to make it out, and I’m happy I did,” said French-American model and actress Camille Rowe in the audience.

Her most coveted Cartier item? “My mom has a 1930s Cartier watch, and I’m so obsessed with it,” she said. “I want it so bad. I don’t really wear jewelry, and that’s the one thing I really, truly want.”

And here we were, celebrating the launch of Cartier’s newest watch. “Really? Amazing,” she said.

Laura Mulleavy, Kate Mulleavy and Kirsten Dunst attend the Panthere de Cartier Party.

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In fairness, there was no indication what the party was for exactly. But when Cartier throws a event, no matter the occasion, people will show. Hosted by Sofia Coppola alongside CEO Cartier International Cyrille Vigneron and President and CEO Cartier North America Mercedes Abramo, the night brought out a roster of Hollywood faces and a who’s who of fashion personalities.

There was Coppola muse Kirsten Dunst, who walked in with Rodarte’s Kate and Laura Mulleavy, Lily Collins, Haley Bennett, Dita von Teese, Arizona Muse, Dree Hemingway, Marilyn Manson, who kept a low profile, and rising actress Sasha Lane, who brought her brother as a date.

“It’s really overwhelming,” she said of the attention she’s received since her breakout performance in American Honey. She was famously scouted by director Andrea Arnold, after the filmmaker spotted the now 21-year-old at a beach in Florida during her college spring break. “It’s very different from what I’m used to, but I find that I can maneuver it pretty well. I do have my brother, I have a lot of friends around me, who help me and support me. I think I’m here for a reason, so while it gets hard, I think, you know, I just gotta keep pushing or make a difference.”

Tonight, she was looking forward to being out, after recently wrapping filming on Shotgun, directed by Hannah Marks and Joey Power. "[I’ll be out] probably pretty late,” she said. “I have some other things to go to as well, so I’m kind of excited. I mentally prepared myself to actually have fun.”

Sofia Coppola arrives at the Panthere De Cartier Party.

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Across the room by the bar was French actress and director Julie Delpy .“Apparently people are flying from all over the world to be here,” said Delpy, now based in L.A. “It was a five minute drive for me.”

“It’s a beautiful brand for be at an event for,” she continued. “I don’t own any Cartier, because I’m an independent filmmaker, so, you know, that says it all. But I look at it!”

Someone who indeed flew in that day was Poppy Delevingne, who recently celebrated her 31st birthday. “I just got off a flight from London,” she said, adding that she was also in town for the premiere of her first film, Guy Ritchie's upcoming King Arthur: Legend of the Sword.

So, what’s a lesson she’s learned that she would give her 20-year-old self?

“Take your makeup off before you go to bed, wish I did that,” she said. She paused. “For me, when I was 21, acting felt so—I never thought I could achieve it. I always pushed it to the back, and I wish I had done it earlier. I’m doing it, and it’s amazing, but I wish I was doing it at 21. Although at 31, there is something about being a little older and more comfortable within yourself.”

Dakota Johnson and Sienna Miller attend the Panthere de Cartier Party.

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She’s now concentrating on acting full time, she said, shortly before making her way back to her table, where Sienna Miller and Dakota Johnson were in deep conversation. “That’s all I’m doing now. I’m giving my full 100 percent.”

Unsurprisingly, Delevingne, who was donning a $25,200 yellow gold “Juste un Clou” necklace at the moment, has been wearing Cartier jewelry since she was a little girl.

“It’s so iconic as a brand,” she said. “You just have to look at one of their red leather boxes and just fall in love with it.”

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