Fanning explained how, in order to make the music video for the film, she had to rapidly lip-sync some of the lyrics to pull off the slow-motion segments. “If they want to shoot in slow-motion, they have to speed up the lyrics that you mouth to and you have to mouth the lyrics super super super fast like Alvin and the Chipmunks style,” she said. That way, when it’s played back, “it looks normal.”
The actress brought a clip of her doing this to show Fallon’s audience, but the late-night host wanted to have more fun with the concept. So they speed sung their way through Carly Rae Jepsen’s “Call Me Maybe,” The Jonas Brothers’ “Sucker,” and Ariana Grande’s “7 Rings.”
Fanning emerged as the all-star of this challenge, no doubt because she’s had a ton of practice as a speedster lip-syncing champ.
Teen Spirit stars Fanning as Violet, a girl looking to escape her small town by entering a local singing competition. Because of that, Fanning gets to sing songs like Annie Lennox’s “Little Bird” and Ellie Goulding’s “Lights.” Plus, you’ll get to see the fruits of her speed-singing labor in the music video that will run over the credits.