Before Ariana Grande was a dangerous woman, even before she was so into you, into you, she was a total theater geek—just like us. When she visited The Tonight Show Starring Jimmy Fallon on September 8, she confirmed she remains as such, and is totally fangirling out over her role as Penny Pingleton in NBC's highly anticipated Hairspray Live! "I heard they were doing Hairspray Live!, and I had a heart attack because this has been one of my favorite musicals," Grande said. "To be playing Kerry Butler's role—it's very overwhelming." We absolutely can't wait to see this starry cast start the beat on December 7! In the meantime, watch Grande fan out below!