Despicable B (S05E21)

Blair feels like her Upper East Side status might be slipping away and devises a plan to assure that doesn't happen. Meanwhile, Lily throws a family gathering -- including William (recurring guest star Billy Baldwin), Carol (recurring guest star Sheila Kelly) and Lola (recurring guest star Ella Rae Peck) -- in an attempt to prove the van der Woodsen family is as united as ever. Finally, Nate digs into Diana's (recurring guest star Elizabeth Hurley) past and is surprised by what he discovers. New York Social Diary's David Patrick Columbia appears in the episode as himself. (Warner Bros. UK)