3.10 "The Last Days of Disco Stick!" - Episode تفصیل 

GUEST PERFORMANCE BY LADY GAGA! — Hoping to impress the elitist theater kids at NYU, Blair (Leighton Meester) sets her sights on landing a private concert with the hottest musical performer of the year, Lady Gaga. Dan (Penn Badgley) and Olivia (guest star Hilary Duff) sign up to write and star in a school play, based on an idea by Blair and directed by Vanessa (Jessica Szohr). With Blair out of the picture, Serena (Blake Lively) turns to Nate (Chace Crawford) to help her get through a difficult situation. As a favor to Chuck (Ed Westwick), Jenny (Taylor Momsen) agrees to hang out with Damien (guest star Kevin Zegers), the son of an ambassador who is staying at Chuck’s hotel, but the experience proves to be a lot more intriguing than she expected.Kelly Rutherford and Matthew Settle also star. Tony Wharmby directed the episode written by Leila Gerstein (#310)

This seems like an interesting eppie.
PLUS, Lady GaGa performing... can't wait!!

Oh wow this ep looks really exciting can't wait for Lady GaGa. :)