Source: http://www.funnyordie.com

Jewel disguised herself as a frumpy businesswoman named "Karen" at a Santa Monica karaoke bar and blew everyone away when she performed her own songs, unknown to the crowd! She finally 'fessed up it was her, but not til after she belted out "Who Will Save Your Soul" and "Foolish Games."

Check out the video and the reactions from the crowd: http://www.funnyordie.com/videos/4a87d48fdd/undercover-karaoke-with-jewel?rel=player