Mick Jagger, Pharrell Williams, (wearing CHANEL)

Billy Farrell/BFA.com

Time stops when Beyoncé enters a room.

Or so it seemed when the very pregnant megastar, in a skintight teal dress by Nicole Miller, and husband Jay-Z made an appearance at The Weinstein Company’s annual pre-Oscar dinner party on Saturday night—the eve of the 89th Academy Awards—at the Montage in Beverly Hills.

This year, host Harvey Weinstein, alongside Marchesa designer and wife Georgina Chapman, honored Lion, up for six Oscars, including Best Picture, and throughout the night, the attention was centered on the film’s stars Nicole Kidman and Dev Patel, up for Best Supporting Actress and Best Supporting Actor. That is, until entertainment’s biggest—and expecting—powerhouse couple walked in.

“Beyoncé? Nothing else matters at this party now," exclaimed a guest.

The two arrived towards the end of the evening just in time for dessert—an espresso martini served with a vanilla caramel budino and chocolate cake, courtesy of sponsor Grey Goose—as In the Heights’ Cynthia Erivo, Chris Jackson and Corbin Bleu closed down the dinner performing numbers from the studio’s film adaptation of the Tony Award winning musical by Oscar nominee Lin-Manuel Miranda, who introduced the performance.

Soon, Weinstein took the stage. “Let’s play the first five minutes again,” he said. What the studio head wants, he gets, and instantly it was déjà vu as the music began again—all for Bey and Jay, of course, who had missed the beginning of the set.

Also in the audience was, interestingly enough, rumored "Becky with the good hair” subject Rachel Roy, as well as Lion director Garth Davis, Nicole Scherzinger, who performed Sia’s "Never Give Up" from the film’s soundtrack, actor Édgar Ramírez, model Petra Němcová, Christian Louboutin, Matthew Morrison and Kelsey Grammer (both of the Weinstein-produced Broadway show Finding Neverland) and Zac Posen.

“I work with the Weinstein family on Project Runway,” explained the designer. “I’m going on my sixth season on the show.”

“High five,” chimed in Golden Globe winner Tracee Ellis Ross, his date for the night, as a salute to his TV milestone.

Posen, of course, is no stranger to the Oscars circuit, having dressed many celebs for the big night in years past.

“Listen, it’s an honor when anyone wears you,” he said. “I never expect anybody to wear my clothing. I don’t feel the pressure or anticipation I did when I was younger when I started out over 15 years ago when I first came out here. When a dress is right, and it has the right moment on the right person, and they feel wonderful and elevated, then it’s meant to be.”

Earlier in the night, another red carpet-favorite, Chanel, and Charles Finch were hosting a dinner of their own, an annual star studded affair, where Kidman had made an appearance for pre-dinner cocktails.

The actress, in an haute couture pastel green satin hobble dress, was one of the many guests dressed by the French house, including Naomi Watts—who spent most of the evening intimately chatting away with Kidman—Ruth Negga, Hailee Steinfeld, Janelle Monáe, Lily Collins, Sofia Boutella, Poppy Delevingne, and Priyanka Chopra, as well as Chanel ambassadors Pharrell Williams, Kristen Stewart and Nocturnal Animals’ Ellie Bamber, who wore a blue leather jacket and skirt.

“I took it from another jacket and put it on,” said Bamber of her belt, which Stewart, who opted for a leather jacket and cashmere top with a silk and lace skirt, was admiring. The buckle was hard to miss with “Chanel” written boldly across the front.

It a tight squeeze inside the packed restaurant, Madeo, where a mariachi band stood on the staircase welcoming guests, which also included Mick Jagger, Adrien Brody, Jamie Dornan, Matthew Modine, Michael Keaton, Alice Eve, Harry Connick Jr., as well as Stewart’s controversial old beau Rupert Sanders and rumored current girlfriend Stella Maxwell.

Consider it the official kickoff to a weekend that's sure to be filled with many awkward, A-list ex encounters.

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