The Billy Joel-Jimmy Fallon duet that Tonight Show viewers saw on last night’s show? A cover of the Rolling Stones’ “Beast of Burden.” But the real treat from last night’s show was an all-star duet that didn’t even make it on-air. While shooting promos for the episode with Joel and Fallon, fellow guest J.K. Simmons suggested the singer play one of this most beloved hits, “The Longest Time.” – USA Today

Here is a portion of Billy’s interview. The full episode can be viewed at The Tonight Show Starring Jimmy Fallon website.

Check out exclusive photos below!

Interview Segment

Billy Joel backstage at The Tonight Show Starring Jimmy Fallon with Carl Fischer, Andy Cichon, Dave Rosenthal, Mark Rivera, Mike DelGuidice, Chuck Burgi and Tommy Byrnes.

Billy Joel backstage at The Tonight Show with Tommy Byrnes, Mike DelGuidice, Chuck Burgi, Mark Rivera, Crystal Taliefero, Dave Rosenthal, Carl Fischer and Andy Cichon.

Billy Joel backstage with Tommy Byrnes, Mike DelGuidice, Chuck Burgi, Mark Rivera, Crystal Taliefero, Dave Rosenthal, Carl Fischer and Andy Cichon.

Billy Joel performs “Beast of Burden” with Jimmy Fallon and The Roots.

Billy Joel interviewed by Jimmy Fallon on The Tonight Show.

Backstage photos by Claire Mercuri. Stage photos by Douglas Gorenstein/NBC/NBCU Photo Bank.