Looks like Glee fans' "Teenage Dreams" will be answered on the November 30 episode when breakout star Darren Criss again leads the Dalton Academy Warblers in an a cappella version of a recent radio hit. With Kurt (Chris Colfer) defecting to the all-male private school's singing team, Criss now has another friend to support his swooning vocals as he takes on Train's "Hey, Soul Sister." Get a preview of the performance below!