Fashion's biggest night is delivering on its promise to showcase "costume art."

Celebrities have started descending upon the steps of the Metropolitan Museum of Art in New York City, wearing attire that fit the evening dress code: "depictions of the dressed body throughout art history."

Grammy legend Beyoncé, Oscar-winning actor Nicole Kidman and tennis star Venus Williams are co-hosting the evening alongside magazine executive Anna Wintour, who has long helmed the event.

This year, Amazon founder Jeff Bezos and his wife, Lauren Sánchez Bezos, also serve as honorary co-chairs.

Here's a look at some of the most daring looks.