It’s Broadway Week on Late Night With Jimmy Fallon and on February 21 the funnyman welcomed the cast of the lush revival of Porgy and Bess to perform. David Alan Grier delivered a rousing rendition of the toe-tapper “It Ain’t Necessarily So.” In the number, the no-good Sporting Life (Grier) reinterprets the Gospel for the townspeople of Catfish Row. Check out the always hilarious Grier along with the company of Porgy and Bess, then see them live at the Richard Rodgers Theatre.