Lady Gaga popped up unexpectedly at a Louisville gay bar called "Connections" and joined a Lady Gaga impersonator on stage, according to media reports Tuesday.

After performing a sold out show at the KFC Yum! Center in Louisville on Saturday night, Lady Gaga made a fashionable entrance in a black leotard, black see-through pantyhose, round black-and-gold sunglasses and super-high stilettos at 1:15 am.

She headed upstairs to say hello to performers and "stopped by every one of the dressing rooms and took photos with them," according to Jason Wetsbay, marketing director for "Connections."

The climax came when the Grammy winner came on out to sing her song "Born This Way," with Gaga impersonator Vanessa DeMornay.

“She dove off the stage into the audience.” Westbay said. “It was standing-room only and the place just went crazy.”

Videos of the performance are on YouTube, TMZ and Perez Hilton.