Glee, S2-E17: A Night of Neglect

Sue tries to derail the New Directions' fundraising efforts to pay for their trip to New York City and for the Brainiacs to go to the Academic Decathlon finals in Detroit.

She assembles several of the glee club's antagonists - Dustin Goolsby (Cheyenne Jackson), director of rival glee club Vocal Adrenaline, Terri Schuester (Jessalyn Gilsig), ex-wife of New Directions' director Will (Matthew Morrison), and Sandy Ryerson (Stephen Tobolowsky), Will's predecessor—to form what she calls a "League of Doom." Will's relationship with Holly is strained as his feelings for Emma get a renewed boost when he learns Carl has left her.

Source: TV Fanatic