Sara finishes confronting Peter about what he's on, while outside Marly is having to explain to Tony why she just can't forgive her mom yet for what she put them through. "With my mother, it's always about what's convenient for her," she tells Tony. Then Marly and Tony encounter Will and Vivian, who says she's upset over something Marly's brother did. In the men's room, Mackenzie quizzes Brian on why he was planning to ditch Zoey and the engagement party - is he cheating on Mac's sister? Zoey knocks on the door of the men's room.