Last night on "America's Got Talent," John Bernhardt of Somerville, MA wowed the judges with his unique cover of The Clash's "Should I Stay or Should I Go," which he performed with a Theremin. Not sure what a Theremin is? Watch the video below and find out what all the fuss is about. 

Even Simon Cowell was amused by the performance, cracking quite a few smiles along with fellow judges Mel B. and Howie Mandell.

Host of "America's Got Talent," Nick Cannon coudln't resist singing along to the song and rocking out.

Will Bernhardt leave his dayjob as an actuary to pursue a career as a Theremin player full-time?

Only time will tell.