But after a commercial break, Fallon and his musical guests were cozy, back in the studio, where U2, seated on the powder-blue couch, performed an acoustic version of their Oscar-nominated song, "Ordinary Love."
It was a fine ending to a much-assured hour.
"I just want to do the best I can and take care of this show for a while," Fallon told viewers. "If you guys let me stick around long enough, maybe I'll get the hang of it."
No worries. For five years on "Late Night" he was getting the hang of it.
EDITOR'S NOTE — Frazier Moore is a national television columnist for The Associated Press. He can be reached at email@example.com and at http://www.twitter.com/tvfrazier .