Serena becomes suspicious of Dan and Blair spending time together, and has Charlie spy on them to find out why. Blair is ecstatic when Prince Louis Grimaldi comes to New York to find her. Meanwhile, Nate helps Raina find out what happened to her mother, while Chuck’s hopes about his legacy are crushed with the reveal of devastating information from the past. Also, Rufus and Eric try to cheer up Lily by having The Pink Party be held at the penthouse: but the party is not without drama.