Jimmy Fallon and John Krasinski Battle in an Epic Lip-Sync Off

The Office star John Krasinski was on Late Night with Jimmy Fallon on Tuesday, bringing with him a new sketch idea. While Jimmy Fallon and Justin Timberlake have performed The History of Rap on several occasions, Krasinski introduced the idea of a Lip-Sync Off. What's a lip-sync off, you ask? Krasinski and Fallon each picked three songs, and then proceeded to lip-sync their hearts out to those songs. Krasinski "sang" Katy Perry's Teenage Dream. That's all you need to know.

Check out Fallon and Krasinski's Lip-Sync Off after the jump.