On Feb. 10, David Letterman stopped by “The Tonight Show Starring Jimmy Fallon” while his former bandleader, Paul Shaffer, and his World’s Most Dangerous Band filled in for the Roots.

David Letterman - with help from some flour tortillas - made a return to the late-night stage Monday. Letterman crashed Jimmy Fallon's Tonight Show monologue Monday night, wandering onto the stage ...

David Letterman ... the band were filling in for the Roots as they prepared for the massive Saturday Night Live anniversary event at Radio City Music Hall. “Paul and I used to do a show almost ...