Rihanna and A$AP Rocky rule the Met Gala

Rihanna, one of the most anticipated Met Gala stars, arrived fashionably late about 45 minutes after the rest of the guests had gone inside. The "Diamonds" singer wore an oversized black coat dress, topped off with a beanie.

The invitation-only Met Gala is a fundraising benefit for New York's MOMA and also marks the opening of the Costume Institute's annual fashion exhibition which this year is titled "In America: A Lexicon of Fashion."