Greta Gerwig on how old Hollywood and disco inspired Barbie

The works of Cary Grant, Rosalind Russell, Gene Kelly, and Debbie Reynolds are among the old Hollywood influences behind Greta Gerwig's Barbie.

From EW's Around the Table interview with the cast, Gerwig and Margot Robbie, the director's star and fellow producer, look back at attending movie church with the crew every Sunday at Notting Hill's Electric Cinema in London during the early days of production. Classic soundstage musicals would project on the big screen and serve as references for the cotton candy pink world of Barbie.

One particular Sunday after the Barbies had a sleepover at Claridge's Hotel, Robbie recalls, the crew gathered for a screening of the 1940 romance comedy His Girl Friday, which she says "had a lot to do with the rhythm of the dialogue" in their film. Singin' in the Rain (1952) and Oklahoma! (1955) were other hymns in the Barbie movie church gospel, informing the movements and dance numbers, led by choreographers Jennifer White and Lisa Welham, for the Barbies and Kens, as well.

Warner Bros. Pictures Margot Robbie in 'Barbie'

"In terms of how they moved and how they behaved, I wanted it to feel heightened, but I didn't want it to feel like a sketch," Gerwig says. "In soundstage musicals like Oklahoma! or Singin' in the Rain, there's a quality in the way people move." All the background actors, Gerwig shares, were actual dancers. "So all the Barbies and Kens you see on the beach [and other dance sequence settings] hold themselves differently," she continues. "Our choreographer said dancers, their bodies always have a direction that's different [from] normal people. So that was kind of like in this conception of Barbie Land, it's like a soundstage musical."

In the first big musical sequence, the Barbies and Kens gather after the best day ever (though every day in Barbie Land is the best day ever) and dance the night away — appropriately to Dua Lipa's "Dance the Night," a disco pop track produced by soundtrack helmers Mark Ronson and Andrew Wyatt. It marks a major moment in the story when Robbie's central Barbie momentarily brings the festivities to a halt to ask, "Do you guys ever think about dying?" Gerwig, a disco enthusiast, knew right away that she needed to include the genre, explaining that it "felt really related to Barbie in its heart because it's so hopeful about people." She says, "Disco assumes you want to dance. That's not the assumption that every musical genre makes."

To enlist the musical stylings of Dua Lipa, who plays Mermaid Barbie, for the big disco dance track felt particularly natural given the source material, which is centered on Barbie as she experiences a full on identity crisis, setting her on a journey of self-discovery. "Dua Lipa makes kind of modern, tragic disco hits," Gerwig observes. "She has that ability to write a disco song that's so much fun, but when you actually listen to it, you're like, 'She's sad.'"

Warner Bros. Pictures Kingsley Ben-Adir, Ryan Gosling, Margot Robbie, Simu Liu, Ncuti Gatwa, and Scott Evans in 'Barbie'

Issa Rae, who plays President Barbie, however, still hasn't quite forgiven Gerwig for that big dance number, revealing that she only had a small window of time to learn the moves. "I just didn't think the president would have to dance," Rae says. Perhaps more nerve-wracking, she'd have to perform it on her first day. The Insecure star was game, learning the ins and outs of the sequence with the help of some friends. But once she arrived on set, she learned the choreography had changed. "I learned it that day and in front of everyone," Rae recalls. "So it was like the first day of school and I was naked."

America Ferrera, for her part, would have gladly stepped onto the dance floor. As Gloria, a human who becomes Barbie's confidant in the real world, the Ugly Betty star didn't get to participate in the dance number — but that didn't stop her from learning the choreography. "I just waited for someone to, like, have to go to a wardrobe fitting. I'm like, 'I'll do it!'" she jokes.

"My only sadness is you guys didn't get to be in the dance," Gerwig says, pointing to Ferrera and Kate McKinnon, who, as ostracized Weird Barbie, was also excluded from the sequence. The Saturday Night Live alum quips in response, "I'm not. I appreciate whenever I'm left out of a dance number, because I find that the worst thing that could happen to me."

Watch Gerwig and co. discuss movements and the dance sequences above. And check out the full Around the Table interview below, with Michael Cera and Ryan Gosling.

Barbie dances into theaters July 21.

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