When it came to translatingBillie Holiday’s iconic, glamorous style to the screen for his upcoming Hulu biopicThe United States vs. Billie Holiday, directorLee DanielstoldVoguehe turned toAnna Wintourfor advice.

After the magazine’s editor-in-chief suggested Prada, nine looks were born thatAndra Day, who portrays the legendary jazz singer, wears throughout the film — and Daniels' favorite is the gownin the “All of Me” performanceat the end, a sketch of which was provided to PEOPLE.

The drawing depicts a floor-length, cap-sleeve gown featuring an intricately embellished bodice and blush-pink tulle skirt.

Prada sketch forThe United States vs. Billie Holidaycostume dress.Courtesy Prada

Courtesy Prada

“I dropped in on most of the fittings and I was involved on all tests with final notes where necessary,” says Daniels, 61, noting that he believes Holiday’s fashion legacy still lives on today. “Tailored clothing and glamour are timeless elements of style.”

As “such a fan of Billie’s,” Day, 36, “was completely obsessed with every single piece, as we spent countless hours on Billie’swardrobe to ensure the pieces in the filmmatched the outfits and gowns Billie actually wore in real life,” Daniels adds.

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From L to R: Lee Daniels; Prada sketch forThe United States vs. Billie Holidaycostume; Andra Day as Billie Holiday.

Lee Daniels' Prada collaboration

The Oscar nominee shares with PEOPLE one fun story about a particular vintage piece that costume designer Paolo Nieddu, Daniels' longtime collaborator, took it upon himself to bring to life, before Day even wore it for the film.

“We were preparing to shoota really emotional scene on set andmy costumer Paolo came to my trailer to show me what Billie would be wearing — specifically, there was a gorgeous vintage gown with fringe, and I wanted to see how it would look on screen since Billie would be moving frequently throughout the scene,” Daniels recalls.

“Without hesitation, Paolo ripped open the garment bag, threw the dress on and sprinted around reciting Billie’s dialogue – which made me break out in laughter,” he adds. “It was such a fun moment and believe it or not, really helped me envision the scene, so it was a win/win.”

Of Holiday’s signature flower shown in Day’s hair atsome points throughout the filmand not others, Daniels tells PEOPLE, “In real life, [Billie] chose to periodically wear the gardenia. We just followed suit.”

Andra Day inThe United States vs. Billie Holiday.Paramount Pictures

THE UNITED STATES VS. BILLIE HOLIDAY Andra Day

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As for Wintour, 71, Daniels recently toldVoguein an interview published Tuesday that “she knew I couldn’t go wrong with Prada” to bring Holiday’s style to life.

“I was going to throw myself at Miuccia [Prada]’s feet as she’s a genius, but I didn’t have to. She admired my work, and I am such a fan of hers, so we were excited,” he added.

Nieddu toldVoguethat during the collaboration process, he “went through every single collection on Vogue Runway then started eBaying vintage magazines because I wanted to flip through a magazine rather than print an image.”

The United States vs. Billie Holidaydrops Feb. 26 on Hulu.

source: people.com