Chuck (Ed Westwick) offers to throw a wedding for a very pregnant Dorota (guest star Zuzanna Szadkowski) who insists that she and Vanya (guest star Aaron Schwartz) have a traditional wedding before her parents arrive from Poland and find their daughter pregnant and without a husband. Dorota asks Blair (Leighton Meester) and Chuck to be part of the ceremony and walk her down the aisle. Serena (Blake Lively) tells Nate (Chace Crawford) she is having breakfast with the Humphreys when in reality she's secretly meeting up with Carter Baizen (guest star Sebastian Stan). Rufus (Matthew Settle) discovers that Lily (Kelly Rutherford) has been lying to him about her whereabouts.