The Boss was in the house.

The crowd that gathered at Duke University's Page Auditorium expected to hear Rosanne Cash and Mark O'Connor perform. Cash was singing songs from her CD "The List," which includes a duet with Bruce Springsteen.

On tour, Cash's lead guitarist normally fills in for Springsteen. Thursday night, however, Cash announced that Springsteen's vocals would be sung by ...

Springsteen walked on stage, and the crowd erupted: Bruce! Bruce! Bruce!

He stayed just long enough to join Cash in singing "Sea of Heartbreak."

He didn't say why he happened to be in the Bull City, just that he was visiting Duke.

A handful of other special guests joined her on the CD, including Elvis Costello for "Heartaches by the Number."

Alas, Elvis was not in the building.