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IN CUSTOM VIVIENNE WESTWOOD
McMillen set a glamorous tone for Elle's Cannes looks by choosing this Westwood design for her first event, the Ismael's Ghosts premiere. She turned to the iconic British label's designs because they are "super flattering and give a sexy, feminine silhouette." This one was custom created for the star, and will go on display at the Vivienne Westwood N.Y.C. boutique in July, the label tells PEOPLE.
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IN CUSTOM VIVIENNE WESTWOOD
Elle "wanted something bold on the back," says McMillen, "so Vivienne's team suggested hand painting. We loved the idea and gave them some inspiration. The rest is history!" In fact, the gown's design featured all of Elle's favorite things, including a shooting star with her name on it, galatic imagery and even a unicorn, which is McMillen's nickname for the actress. "Unicorns are special, magical, mythical sparkly creatures. I think of Elle as that. I always have," she says.
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IN MIU MIU
McMillen says she loves to look for things that "have unique or special details" and if look closely at this Miu Miu design, there are telephones on it! She paired the look with white heeled mules and standout rosy shades.
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Fanning, who was celebrating her new gig as a L'Oreal ambassador in addition to her films at the festival, wowed again at the premiere of How to Talk to Girls at Parties when she chose this floral green Gucci gown. While it looks demure from some angles, others show off a backless design and some side boob exposure. She captioned the look on Instagram as "Floating on flowers!"
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Fanning and McMillen played up their affinity for fun and quirky details when they chose this mod-inspired Prada shift and platform heels for the official How to Talk to Girls at Parties photo call.
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The star and McMillen combined Miu Miu danglers with a feathered Prada dress and satin mules for the a private Prada dinner. This mix is especially trendsetting because on anyone else it would be nearly impossible to pull off.
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IN CHRISTIAN DIOR HAUTE COUTURE
The flowers on the Dior gown Fanning wore to the 70th Anniversary Gala are actually made of feathers, which is amazing enough, but couple that with the fact that it's couture, which means that every single stitch is hand-sewn. The sheer amount of work it must have taken to create this gown is mind-boggling.
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IN ALEXANDER MCQUEEN
Fanning looked like a modern-day prairie girl in this white Alexander McQueen look, which she paired with multi-colored black peep-toe heels for The Beguiled photo call.
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For her final look, McMillen and Fanning worked with Rodarte designers Kate and Laura Mulleavy to create this pale purple strapless gown, which was inspired by the artist Edgar Degas's famous ballerina series. Fanning gave a shout out to the designers on her Instagram: "You asked to make me my dream dress and that is exactly what you did!!!!! So many layers of lavender love!!!" Chanel jewels finished the look.
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THE STAR AND HER STYLIST
Samantha McMillen showed her love for the star in a thoughtful and sweet Instagram post after their final red carpet look of the festival. "Thank you my darling Elle for taking me along on this amazing journey with you," she said. "You are an incredible collaborator, an inspiration always. You are fearless on the red carpet and captivating and brilliant on the screen. I am so proud of you and I'm so happy that we were able to come and create some magic here in Cannes. I love you, Unicorn."