Glee Season 3 Episode 8 : Hold On to Sixteen

Sam Evans (Chord Overstreet) returns to McKinley High and New Directions at Finn's urging just in time to compete in Sectionals—hosted by McKinley—against stiff competition, which includes McKinley's Troubletones and the Unitards, fronted by Harmony (Lindsay Pearce). Quinn makes a pivotal decision, and Sebastian plans a second try for Blaine. Tina helps Mike and his father come to an agreement about Mike's college plans.