Blair (Leighton Meester) gets ready for her mothers (guest star Margaret Colin) imminent arrival, but is unprepared for the set of demands her mother puts upon her. Serena (Blake Lively) volunteers to help Dan (Penn Badgley) find a new place to live, but their time together brings up unexpected emotions. With Ivy's (Kaylee DeFer) help, Chuck (Ed Westwick) discovers there is evidence incriminating his father in illegal activities and enlists the help of Nate (Chace Crawford) to retrieve it. Meanwhile, Rufus (Matthew Settle) and Ivy are excited about their art gallery opening until they find an empty RSVP list and must scramble to find another way to make the event a success.