In the movie “The Substance,” Demi Moore plays an entertainer in her 50s so intent on hanging onto stardom that she signs up to take a potion that will restore her youth, but at a horrific price.

“This is more joyous,” Ms. Moore said of the beautification process leading up to W Magazine’s Golden Globes party held on Saturday evening, the night before the ceremony, in a top floor suite of the Chateau Marmont hotel in West Hollywood.

She was decked out in a black and white polka-dot dress from Nina Ricci as she stood in a tented area where the smell of cigarette smoke was surprisingly strong and household-name celebrities and fellow Globe nominees were everywhere.

The party, co-hosted by W’s Magazine’s editor in chief Sara Moonves, and its editor at large, Lynn Hirschberg, was celebrating the magazine’s annual Best Performances issue, and the walls were covered with enlarged photographs of the featured celebrities.

On one side of the room, the real-life Nicole Kidman stood underneath a giant image of the actor Daniel Craig, nominated for a Globe for his role in the movie “Queer.” On the other side, the real-life Mr. Craig, in a pair of tinted glasses, a black shirt and wide trousers, stood beneath a giant image of Ms. Kidman, who was nominated for her part in the film “Babygirl.”

“Not a bad year,” someone said to Ms. Kidman as she made her way through the crowd with her daughter Sunday Rose Kidman-Urban.

“Not a bad year, indeed,” Ms. Kidman said as a DJ played Blondie’s Rapture while Sabrina Carpenter and Cynthia Erivo shimmied by.

Did Ms. Erivo, who is up for a Globe for the film “Wicked,” have an outfit picked out for the next evening?

Of course she did.

“LV,” she said, by which she meant Louis Vuitton. Nicolas Ghesquière, the artistic director women’s collections at the brand, happened to be out on the terrace, a few yards from Ms. Moore and within spitting distance of Angelina Jolie, a nominee for her performance in the film “Maria,” in which she plays the opera diva Maria Callas.

She seemed to be the only attendee who had a handler stopping photographers from taking pictures of her. But a moratorium on her moratorium took place when Ms. Moonves ambled over to say hello and to politely make it clear that, for history’s sake, the moment would be captured.

Kevin Mazur, a celebrity photographer for Getty Images, raced through the crowd with his camera. The pop stars Charli XCX and Ms. Carpenter huddled together with the model and actress Cara Delevingne.

By 10 p.m., the place was so crowded that the designer Christian Louboutin realized he was going to have to leave the penthouse suite for his room elsewhere in the hotel.

But only for a moment.

“I have to pee!” he said.

“You can get in but you can’t get out,” said Pamela Anderson, who was by the door, hoping to make an exit.

And who could blame her?

After all, Ms. Anderson is featured in the magazine’s issue and is nominated for a Globe for her role in the film “The Last Showgirl.”

Clearly, she had a full weekend ahead of her, although so did the celebrity stylist Law Roach, who seemed to have no interest in leaving.

What was his client Zendaya, nominated for the movie “Challengers,” wearing to the awards the next evening?

“Vuitton,” he said, adding that the jewelry would be Bulgari and that the whole look would be inspired by Joyce Bryant, the glamorous Black singer of the 1940s and ’50s who broke racial barriers in nightclubs.

A few feet away, Eddie Redmayne, nominated for his role in the television series, “The Day of the Jackal,” was hanging out with Andrew Garfield, who is scheduled to present at the Globes.

Colman Domingo, nominated for his part in the movie “Sing Sing,” mingled with Tilda Swinton, nominated for her role in the film “The Room Next Door,” and then headed to the dance floor around the time that DJ Ross One began pumping Shannon’s “Let the Music Play.”

Around 11:30 p.m., the party was still going strong. Waiters paraded around the room with chocolate truffles and French fries.

Kevin Bacon, with his wife, Kyra Sedgwick, was by one of the sofas inside the suite wearing a blazer and a vintage Iron Maiden T-shirt. It was one of only a few outfits not selected by a stylist.

“My son got it for me for Christmas,” he said.