Stephen S. Lash , chairman of Christie 's Americas , invited 800 of the auction house 's closest friends -- the likes of Bobbi Brown , Dominick Dunne , Kitty Carlisle Hart , Jeff Koons , Wilbur L. Ross Jr. , Stephen A. Schwarzman and Mortimer B. Zuckerman -- to a black-and-white ball at Christie 's Manhattan headquarters to commemorate the 40th anniversary of Mr. Capote 's legendary ball at the Plaza Hotel .