The couple kick off a joint celebration in Los Angeles. Plus: Britney Spears, Kevin Federline and more

BLUE BELLE

Beyoncé makes a smooth impression in navy Versace at the L'Oréal Legends Gala (which benefits the Ovarian Cancer Research Fund) held at the Museum of Natural History on Wednesday. "I wanted something chic, understated, but still sexy," the singer told PEOPLE of her stunning fashion choice.