Dave Grohl will be co-hosting The Tonight Show Starring Jimmy Fallon on Monday night (May 24).The Foo Fighters frontman’s duties are set to include delivering the monologue, playing games and interviewing the episode’s other guest, comedian Jim Jefferies.While Grohl will be hosting the show alongside main host Jimmy Fallon, he won’t be the episode’s musical guest, this will be country singer Blake Shelton.