NEW YORK – While working on films like Atonement (2007), Anna Karenina (2012) and Darkest Hour (2017), British production designer Sarah Greenwood and British set decorator Katie Spencer, both Oscar nominees many times over, had to turn soundstages into period-accurate sets, using their extraordinary attention to detail to embroider these spaces with texture and soul.

And while those jobs were demanding – if even one thing looked wrong, it could dispel the film’s period illusion – they proved to be no match for the bright pink studio comedy that is American writer-director Greta Gerwig’s Barbie, which is showing in cinemas.

“It was one of the most difficult philosophical, intellectual, cerebral pieces of work we’ve done,” Greenwood said during a video call with Spencer. “How can that be? It’s Barbie. But it really was.”

Then again, since the film works on several levels, many things about Barbie are headier than you might expect. Though it is a big-budget film based on a Mattel toy, Gerwig and co-writer Noah Baumbach pose plenty of significant questions about life and womanhood throughout.

And in the visually dazzling Barbie Dreamhouses that Greenwood and Spencer designed – where Australian actress Margot Robbie, as Barbie, and Canadian actor Ryan Gosling, as Ken, performed – even the smallest details in the background required months of existential pondering.

Spencer said: “Everything is considered. Absolutely everything.”

Though Gerwig came on board the project as a bona fide Barbie aficionado, Greenwood and Spencer had no personal history with the doll.

“Neither of us had Barbie growing up,” Spencer said. “I suppose we were like a lot of the population, quite judgmental about Barbie in a way.”

Still, captivated by Gerwig’s enthusiasm, the two women threw themselves into intense research. Their directive was to preserve a sense of play, which is why Barbie’s home has no stairs. Why would a doll deign to descend a flight of steps when she could take a circular pink slide or float gracefully down from the roof as if guided by the invisible hand of a child?

“We all had to believe in it as much as if it was a space or period movie,” Spencer said. “We had to research it as though it was set in 1780.”

First, the designers studied a vintage Barbie Dreamhouse, finding it to be more cramped than they anticipated. A classically proportioned Barbie could graze the ceiling of each room with a simple upward swivel of her arm.

To simulate that feel, “the Dreamhouses in the film are 23 per cent smaller than they would be, as are the cars and roads”, Greenwood said. “When you scale the house down, you make the actors seem bigger, which makes the whole thing seem ‘toy’.”

Instead of adapting the Dreamhouses to feel more real, Greenwood and Spencer played up their surreality. When Barbie opens her refrigerator, most of the foods are simply flat cartoon decals. Her oversized cup contains no liquid – why should it, when Barbies don’t drink? – and the size of her toothbrush is even more exaggerated, since it is the kind of prop a child might find included in a dollhouse.

Spencer said: “Once you’ve done that once or twice, those moments of dollness, it makes the whole thing believable.”

With few walls to speak of, Barbie Dreamhouses are the definition of “open plan”, which presented logistical problems.

“You’re designing something that isn’t there, in effect,” said Greenwood, who drew inspiration from museum dioramas to conjure layers of background that would help fill each shot.

Since the main Barbies live in a cul-de-sac, each Dreamhouse looks out into several other Dreamhouses, while the blue sky and mauve mountains that surround them were hand-painted onto a 244m-long backdrop meant to recall old-fashioned soundstage musicals.

If it feels artificial, that is the point: Why preserve the fourth wall for homes that barely have any walls to begin with? “It’s fake-fake, which is perfect,” Greenwood said. “It was almost Brechtian, the way Greta approached it.”

There is no actual fire in Barbie’s fireplace, nor water in her pool, since Barbieland is devoid of all elements and is as hermetically sealed as a toy box. There are not even whites, blacks or browns. Anything in a Dreamhouse that would typically be those colours is just a different shade of pink, with a primary fuchsia so vivid that the production cleaned its paint supplier out of every pail they had.

“All the other colours, like the blues, had to up the ante,” Greenwood said, referring to their intensity.

The cul-de-sac Dreamhouses were designed in a mid-century-modern style that evokes the time period when Barbie was invented.

“We kept coming back to the aesthetic of Palm Springs,” Spencer said.

The film was shot in 2022 at Warner Bros’ Leavesden Studios, north-west of London and, as word of the colourful sets spread, the production quickly attracted its fair share of visitors. “We were filming in an English winter, gray and black with snow,” Greenwood said. “So everybody would just go there for an injection of light and summer.”

Added Spencer: “It made people happy. You couldn’t help but smile.”

And what of its makers? Did all that time spent on these Barbie sets affect their personal palette? Yes, confessed Greenwood.

“I’ve painted my bedroom pink,” she said. “I’d never painted anything pink before. I love pink now.” NYTIMES