Billie Eilish Channeled Old Hollywood in Oscar de la Renta at the Met Gala

Met Gala co-chair Billie Eilish went for full Old Hollywood glamour.

Eilish stepped out on the red carpet wearing an ensemble that called to mind Marilyn Monroe, Grace Kelly, and Holiday Barbies, which Eilish said were her favorite as a child. Her peach-colored Oscar de la Renta gown featured tulle cold-shoulder sleeves and a corset waist, trailing out to a full skirt with a 15-foot circular train.

The "Happier than Ever" singer wore her hair in a tousled bob and accented her beauty look with bold black eyeliner and a red lip. She accessorized her gown with thin silver rings and bracelets on both arms.

The "Bad Guy" singer told red-carpet host Keke Palmer that "it was time" for her look, adding that after all this time, she's finally confident in her body. Eilish has been outspoken about empowerment when it comes to fashion. In May, she opened up in a cover story, advocating for more women to own their clothing choices. "Showing your body and showing your skin—or not—should not take any respect away from you," she said.

Eilish's hosting gig comes just one night after her appearance at the 2021 MTV Video Music Awards, during which she appeared on the red carpet in a comfortable, all-black ensemble: a cowl-neck sweater and midi skirt, paired with black leg warmers over matching sneakers. At the awards ceremony, she was presented the Video for Good Award by Avril Lavigne for her song "Your Power" and spoke on women's rights. "We need to protect our young women at all costs," Eilish said. "We also need to remember that we all have power, and we have to remember not to abuse it."