The first Monday in May — also known as the Metropolitan Museum of Art Costume Institute benefit — is what Andre Leon Talley once called "the Super Bowl of social fashion events." You're not going to get the regular ol' cocktail dress, Christian Louboutins, and Dry Bar blowout here. Celebrities go all out for the Met Gala, either adhering to the Costume Institute-designated theme or doing their own thing. On this night, anything goes.