The singer wore a custom Maison Valentino design, a periwinkle gown and cape made of silk faille, designed especially for her by Creative Director Pierpaolo Piccioli (the designer shared a picture of it on his Instagram, with the caption 'Always Remember Us This Way' after Gaga's song in the movie).
Gaga being Gaga, she went all out, accessorising with over 100 carats' worth of diamonds in the form of the Tiffany Aurora necklace, which features over 300 brilliant diamonds, including a radiant 20-carat pear shaped diamond at the heart of the necklace.
She also dyed her hair blue to match the dress.
Opulence aside, there was a hidden meaning behind her choice of outfit. The dress was remarkably similar to the one Judy Garland wore in the 1954 version of A Star Is Born (did you know Gaga is the fourth to take on the role of Ally?).
Hers was designed by Jean Louis, and was a darker shade of blue, but with the same shape and puff sleeves. Although the singer hasn't referenced the similarities, it hardly seems like a coincidence, don't you think?
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Penny Goldstone is the Digital Fashion Editor at Marie Claire, covering everything from catwalk trends to royal fashion and the latest high street and Instagram must-haves.
Penny grew up in France and studied languages and law at the Sorbonne Nouvelle University in Paris before moving to the UK for her MA in multimedia journalism at Bournemouth University. She moved to the UK permanently and has never looked back (though she does go back regularly to stock up on cheese and wine).
Although she's always loved fashion - she used to create scrapbooks of her favourite trends and looks, including Sienna Miller and Kate Moss' boho phase - her first job was at MoneySavingExpert.com, sourcing the best deals for everything from restaurants to designer sales.
However she quit after two years to follow her true passion, fashion journalism, and after many years of internships and freelance stints at magazines including Red, Cosmopolitan, Stylist and Good Housekeeping, landed her dream job as the Digital Fashion Editor at Marie Claire UK.
Her favourite part of the job is discovering new brands and meeting designers, and travelling the world to attend events and fashion shows. Seeing her first Chanel runway IRL at Paris Fashion Week was a true pinch-me moment.
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