The "Schiaparelli and Prada: Impossible Conversations" Costume Institute Gala at the Metropolitan Museum of Art in New York City was the place to be on Monday night.

New mom Beyonce stunned in a sheer black and purple dress that showed off her muscular legs. Rihanna was glamorous in a black form-fitted gown, while an adorable Emma Stone wore a short red cocktail dress.

Other stars shining in their designer duds included a golden Jessica Alba, a regal Scarlett Johansson, and a sparkling Cameron Diaz.

See tons of photos of the stars...