Warning: Minor spoilers ahead for Spencer.

While Jacqueline Durran has worked on a myriad of high-profile projects like Little Women and Anna Karenina, the award-winning costume designer says that dressing Kristen Stewart as Princess Diana for Pablo Larraín’s Spencer was unlike anything else she has done in her impressive 22-year career. Instead of using her creativity within the constraints of a historical time period (see: Little Women‘s and Anna Karenina‘s 19th-century costumes), to stay true to the late Princess of Wales’ style, Durran had to draw from the vast library of images and then narrow it down to select looks.

“There is just a picture that tells you exactly what she wore on each day,” Durran tells Refinery29. “It’s quite overwhelming that there is that much information about her.” Keeping “how much she was photographed and what that must have felt like,” in mind, Durran created looks that don’t just stand out visually but support the film’s plot.

Set in 1991 at the Queen’s annual Christmas retreat at Sandringham, Spencer follows Princess Diana through the three-day festivities, just as she’s coming to terms with the effects that royal life, her marriage to Prince Charles, and global celebrity had on her, including depression, anxiety, and bulimia. (Diana and Charles separated the following year.) As with any royal outing, the events at Sandringham called for a formal dress code, which the film explores, pinning Diana’s personal style preferences against that of the Windsor family.

Although the film is set in a specific year, Spencer is a fictional depiction of the events that took place — the film opens with this line: “A fable from a true story” — which is why Durran was likewise able to play around with Diana’s costumes, pulling references from both her style as a royal and her post-divorce wardrobe. “You can see that it’s not at all exact,” she says. 

When preparing for the film, Durran, who grew up in England at the time that Princess Diana entered the Royal Family, looked at Diana’s style with new eyes, researching images from her 15 years as Princess of Wales. “I think that in itself can become slightly overwhelming because there’s so much reference,” she says. To avoid that, Durran didn’t copy the exact outfits Diana wore during that weekend and, instead, pulled inspiration from her style more generally. With the help of Chanel, for which Stewart is an ambassador, Durran was able to go through the house’s archive for originals of pieces worn by Diana, as well as modern jewellery, handbags, and accessories. 

One example is the look seen in the movie’s poster, in which Stewart wears a red coat (top photo) that Durran sourced from the Chanel archives. For this scene, Durran nodded to a similar look that the late Princess wore to Christmas Day service at Sandringham, but in 1993, as well as another red coat that she wore in 1998. Other referential outfits include the sailor-like yellow skirt suit, also seen in the movie’s trailer, which mimics a pleated skirt and suit combo that Diana wore in 1992 and a navy blazer-and-jeans combo, paired with ballet flats and Chanel flap bag, a combination that Diana often repeated throughout the ‘90s. 

But the movie’s most symbolic piece is a pearl necklace, a nod to a similar single-strand style that Diana wore throughout the ‘80s, including to events like a 1983 tour of Canada. “It’s such a pivotal part of the movie,” says Durran. The costume designer worked with jewellery company Mouawad, the brand behind the Miss Universe crown, to sort through several sizes of pearls, settling for a medium-sized set with a gold enclosure. 

The pearl necklace is introduced early in the film, when Stewart’s character starts to feel haunted by the history of Anne Boleyn. The second of Henry VIII’s wives, Boleyn was famously depicted in portraits wearing a B-lettered pearl necklace. In the film, the royal sees Boleyn’s death, at the hands of her husband, as a premonition of what could happen to her if the upper echelons of society ever turned on her. Throughout the film, Stewart wears the necklace — gifted by Prince Charles — for family occasions, questioning whether the piece is similar to the one he gave Camilla Parker-Bowles and even offering it to one of the estate’s maids. In one of most dramatic scenes, Diana breaks the necklace, symbolising her setting herself free from her gilded cage.

In the same scene, she wears a cream-and-gold strapless gown with a tulle skirt, which Durran considers “the key dress” in the film. Sourced from the Chanel archive images, the dress was remade by the house from a Karl Lagerfeld design. The dress bears a resemblance to several of Diana’s real-life outfits, specifically a white-and-gold Emanuel dress the Princess wore in the 1980s. 

During one scene, Diana sees Boleyn’s ghost dressed in a Tudor-style gown, which Durran sourced from the London-based costume house Sands Films. The costume designer pulled the look — modelled after the outfit seen in portraits of Boleyn, on display at the National Portrait Gallery in London — out of existing pieces. “It’s strange when you have one very period thing in the context of a modern film because your head is so totally in the ‘80s,” says Durran of the challenges this scene presented for her. 

While the clothing in Spencer comes loaded with meaning, Durran says she wanted the costumes to serve Stewart’s performance, rather than steal the spotlight. “I think what people should take from the movie is what an amazing performance Kristen gives,” she says. “It was a liberating look at Diana.”

Spencer is released in cinemas on 5th November

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