Billie Eilish just stunned on the Met Gala 2021 red carpet in an old Hollywood-inspired ensemble.

The 19 year old appeared at the fashionable event, themed 'In America: A Lexicon of Fashion', wearing a peach, 1950s-style gown by Oscar De La Renta.

met gala 2021 billie eilish
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The dress featured a full skirt, large train, boned corset and tulle shawl.

billie eilish met gala 2021 red carpet
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Usually seen with a shag hairdo' the 'bad guy' singer wore her newly-bleached hair in a vintage-inspired bob and paired the ensemble with silver bracelets and pearl earrings.

met gala 2021 billie eilish
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The young star explained she was inspired by the Holiday Barbie she owned as a child for the look.

The 19 year old, famed for her oversized streetwear looks, has recently revamped her style, channeling old Hollywood glamour and more specifically Marilyn Monroe with more fitted clothes.

billie eilish met gala 2021 red carpet
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Eilish discussed her historically negative relationship with her body in an interview with Vanity Fair: 'I think that the people around me were more worried about it than I was, because the reason I used to cut myself was because of my body. To be quite honest with you, I only started wearing baggy clothes because of my body,' Eilish disclosed.

'I was in the midst of my horrible body relationship—or dancing a ton, five years ago, I wasn’t really eating. I was, like, starving myself,' she told the publication.

Thankfully, Eilish appears to have grown from her past experience and is embracing her body.

Yara Shahidi, Julia Garner and Maisie Williams joined the bombshell on the red carpet of the fashion event of the year and you can see all their looks here:

Met Gala 2021: The Best Dressed Celebrities On The Red Carpet
met gala 2021 best dressed celebrities