Miranda Priestly's white hair almost didn't come to be, according to costume designer Patricia Field. While both Field and Streep were excited about the idea, the studio was less so, imagining Priestly's hair to be grey. Streep, however, being the legend that she is, stood her ground and the studio eventually relented. "The first time Meryl was Miranda Priestly was a meeting with the head of the studio. Meryl channelled Miranda in that meeting, and there was no conversation about the hair; they looked into Meryl's eyes and never said a word," says director David Frankel. That's all!

Outtakes revealed that Stanley Tucci––who starred as Runway Magazine's cynical art director Nigel Kipling––tried different versions of the zinger when Andy asked Nigel whether she'd fit into a beautiful black sample in the fashion closet. "With a bit of Crisco and a staple gun, we're in business" was what ended up in the film, but they could easily have been fishing wire and duct tape instead. 

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When Emily Blunt was cast as Priestly's first assistant Emily Charlton, screenwriter Aline Brosh McKenna discovered how funny Blunt was and decided to work with her to add Britishisms into Charlton's dialogue. "There's something a bit more imperious that I thought'd be interesting… It was appropriate for her, and something a bit more cutting about it that I found funny," said Blunt. 

Several designers and industry icons were approached to appear in the film, but fearing Anna Wintour's disapproval, all declined, save for supermodel Gisele Bündchen whom screenwriter McKenna saw on the plane. Bündchen was hesitant at first but eventually agreed, under the condition that she played someone other than a model. She became immortalised as Priestly's leggy third assistant.

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In the hopes of making the film more realistic, the creators attempted to infiltrate the Vogue offices, and managed to do so with the help of production designer Jess Gonchor who snuck into Anna Wintour's office. "He was able to re-create the office so authentically that I was told Anna redecorated hers immediately after the movie came out," said Frankel. 

Said Frankel: "There were [initially] no designers of note who would appear in the film. They just didn't want to incur the wrath of Anna. Some of them showed us their showrooms or gave us notes on the authenticity of the script; they just didn't want to participate. Initially, Pat had a hard time getting clothes out of a lot of the designers. I think it was Prada that helped her break the ice and said that Anna's not going to be upset." Wintour, who attended the premiere with her daughter Bee Shafer, also gamely wore Prada. 

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