BILLY BALDWIN ("WILLIAM VAN DER WOODSEN") RETURNS/ANDREW MCCARTHY DIRECTS THE EPISODE - Blair thinks Cyrus (Wallace Shawn, who does not appear in the episode) may have found a potential loophole in her prenup. Chuck and Georgina (Michelle Trachtenberg) partner up in a scheme, but it has an unpredictable outcome. Meanwhile, a family crisis brings William van der Woodsen (Baldwin) back to the Upper East Side. Blake Lively, Penn Badgley, Chace Crawford, Kaylee DeFer, Kelly Rutherford and Matthew Settle also star. Andrew McCarthy directed the episode written by Jake Coburn.