clickables Dec. 6, 2010 Hear Katy Perry Sing a Surprise ‘Teenage Dream’ Duet With Darren Criss By Amanda Dobbins Hmm. You’re allowed to do that when it’s your own song, we guess? [Towleroad] Tags: clickables darren criss katy perry music teenage dream video More Hear Katy Perry Sing a Surprise ‘Teenage Dream’ Duet With Darren Criss