Hidden details (Sylvester Stallone! Faux denim! Horses!) in Barbie's costume design

It's not easy being pink.

Just ask Jacqueline Durran, the Academy Award-winning costume designer behind some of films' most memorable looks (see: Keira Knightley's emerald green Atonement dress and crimson red Anna Karenina gown, to name just a couple), who brings a keen attention to detail to the cotton-candy pink world of Barbie.

The designer, who also outfitted the March sisters in Greta Gerwig's 2019 Little Women remake, reunites with the filmmaker in the comedy starring Margot Robbie and Ryan Gosling. Durran mined from Mattel's storied archives but also put her own twist on the whimsical and incisive ensembles, helping fuel the ever-popular Barbiecore trend this summer season.

Ahead of the film's theatrical July 21 release, Durran also partnered with online consignment shop thredUP to curate a Barbiecore collection. Ranging from accessories to dresses and shoes, the very pink collection features picks from Kate Spade, Stuart Weitzman, Zara, Gap, and more and highlights the designer's love of secondhand shopping. 

Below, Durran walks EW through just a few of the stylish film's most memorable looks. 

At the giant blowout party that features the Barbies and Kens grooving to "Dance the Night" by Dua Lipa (who makes a splashy cameo as Mermaid Barbie), Durran chose a distinct color scheme to contrast the pink of the dreamhouses, something she noticed in Mattel's back catalogs. "There was so much white and gold," Durran recalls. "It seemed like a real Barbie choice for a party."

Robbie's Stereotypical Barbie dons a gold sequined disco jumpsuit, while the Kens wear matching white jogger jumpsuits with golden embroidered Ks and stripes on the side. Both jumpsuits were modeled after retro jumpsuits manufactured between the late 1960s and early '70s. The fabric for the Kens' jumpsuit was a bit difficult to source since it had to be "the right weight and not be too stiff," Durran explains, noting that trying to get them all made in time due to the sheer number of Kens in the scene also caused some anxiety.

"We did interpret and change things slightly," Durran says. "But mainly, particularly with the women and all the kind of strange frills and different lengths and different costumes, all of that's inspired by Mattel." 

When Barbie and Ken arrive in the real world, first rolling into the bohemian California beach town of Venice before making their way to Mattel headquarters in bustling Century City, they sport a pair of matching neon leotard sets and bright yellow rollerblades. Durran once again mined from Mattel history, drawing inspiration from 1994's Hot Skatin' Barbie. 

"The actual way that Barbie wears it then [was] slightly different," Durran says. "We changed the layout a bit, [but] the print is the same, the pattern is the same. Our textile artist copied the original pattern and printed it onto the leotard and onto the pieces for Ryan." Putting together the looks was initially a bit tricky because, as Durran notes, "If you are gonna put a costume on somebody and they're gonna really stand out in Venice, what is that gonna be? You have to go quite far [out] because Venice has so many characters [and] no one really raises an eyebrow." 

"To get people's attention," she adds, "they had to be over the top, so that's why we pushed it this far." For the rollerblades, Durran sourced skates from Impala Skate and painted them a bright neon color — at the time, the brand did not have neon yellow and pink options. As Barbiemania continues to grip the cultural zeitgeist, they certainly do now: Impala has since released a Barbie collaboration of the skates, as well as protective knee padding and socks in the bright hues as seen on Barbie and Ken.

Once the neon leotards proved to be too distracting, eliciting catcalls in the real world, Barbie and Ken opt for Western-themed outfits that evoke the Wild Wild West, complete with matching white cowboy hats. It's an astute nod to the themes of patriarchy and the all-American setting the dolls find themselves in, though Durran admits it was a bit difficult to crack at first. "Now that it's done, it feels entirely obvious and the right costume for the right moment, but it took a moment to work out," she says. "When they arrived in America, what would they wear? How would a Barbie and a Ken — well, not so much a Ken, 'cause Ken follows — but how would Barbie choose what to wear when she wants to fit in and be liked in America? Does she become a Malibu girl?"

When they landed on the pink two-piece (which has since been recreated by just about every fashion vlogger under the real-world sun), putting it together was surprisingly challenging because the team had trouble tracking down pink denim. "We had to buy pink stretch fabric and then print a denim texture onto it," Durran shares. "There were lots of different versions of it, with a waistband, without a waistband. It took a long time just to work, to get the exact details of it." (It certainly paid off, as the outfits will no doubt serve as popular Halloween costumes of choice this year.)

To bring to life the aesthetics of the Kentriarchy, Durran referenced a series of "archetypal masculine" visuals while working out the look of a real-world-corrupted Ken, which brought her to the black leather waistcoat (or vest). "This evolved in the fitting," Durran explains. "There's always something kind of extra in everything that they wear. Another kind of last-minute thing is, we added these fringe shoulder pads and that just finished it off." Ken's all-American male headband that references his love of horses is also one of Durran's favorites. "In another scene he's wearing the tracksuit that matches that and printed onto the tracksuit is horses galloping with lightning," she notes. "And so the headband, that little kind of line going across is from the lightning part of the pattern of the horses. These details with horses and all of these things, I just love the fact that they're all in there." 

The faux fur coat is, of course, "100% inspired" by Sylvester Stallone and the imagery of the Rocky actor featured in the film when Ken comes to the realization that men rule the real world. "Those images were kind of around in the early prep when we were first talking about what Ken would look like," Durran says. "It seemed so extreme and over the top, but also just so brilliant. We were really wanting to get that in as a Ken image. And I wasn't sure, because Ryan hadn't started on the movie yet, whether he would be up for this kind of look or not, but he totally embraced it and he was really happy to have the fur coat."

The lining of the fur coat once again nods to Ken's love of horses. "The lining, if you notice, has a print of horses on it that we printed for him and made," Durran adds. "That's one of my favorite things."

At long last, the pièce de résistance: Barbie's salmon-pink Birkenstocks she wears at the very end of the film as she walks into an office building in her new home of the real world. Turns out, the shoe choice stemmed from the brain of Gerwig rather than Durran. "I can't take any credit for the Birkenstocks," Durran says, sharing that it was embedded in the script from the get-go. "Greta immediately, from the beginning, had the contrast between the stiletto heel and the Birkenstock in the Weird Barbie scene."

In the scene in question, Barbie arrives at Weird Barbie's (Kate McKinnon) eclectic dreamhouse to seek counsel about her malfunction. Among the many odd things she's been experiencing? Flat feeeeeeeet! Her feet are no longer arched, much to the horror of fellow Barbie Land residents. Birkenstocks are a clever nod to the narrative, as the sandals' classic cork and latex footbed has been given the seal of approval from podiatrists for — you guessed it — flat feet and arch pain. 

Barbie is in theaters now.

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