Everyone looked smashingly glamorous, from Isabel Lucas in Proenza Schouler (including the knee-high boots) to Beyoncé, who had been working all day in the recording studio, but decided at the last minute to come to the gala—just an hour before the evening began. Ask the new mom about her baby, Blue Ivy, and she lights up. “She’s four months old today, and she’s just got the most delicious little cheeks,” she said. Jay-Z stayed home, so mother came out solo wearing a Givenchy Haute Couture by Riccardo Tisci sizzler—comprised of feathers and exaggerated black embroidery—that took 350 hours to make.