Cameron Diaz and Colin Firth reunited on the London set of Gambit today. He's home in England after cochairing Monday's Costume Institute Gala alongside Stella McCartney and Vogue boss Anna Wintour. His wife, Livia, shared some good insider snaps from the ladies' room on her Twitter account and also gave British Vogue a behind-the-scenes look at how she and Stella created the ultimate eco look for the bash. Cameron skipped the Met Ball red carpet, but she still seems to be everywhere these days. Her promotional efforts for Bad Teacher have begun, and she's on the cover of magazines ranging from Elle UK to Cosmopolitan. There are even sexy photos of Cameron Diaz in Maxim. She was covered up for her day on the chilly English set, though, and was spotted leaving her trailer in a pair of Uggs.