We've documented David Letterman's obsession with the band the Orwells. But the scruffy Elmhurst, Illinois, rockers may have to move down a notch on the man crush list after what happened on Wednesday night's "Late Show."

You see, that was the night Dave was introduced to British soul pop powerhouse, and MTV Artist To Watch Sam Smith, who performed his hit "Stay With Me" on the show. After the string- and mini-gospel choir-infused greatness that is the 22-year-old rising star's signature hit, all Letterman could say was "wow" (twice) and "beautiful" and "oh my God."

See for yourself: