Take it from a Billy Joel skeptic who caught his headlining set at Bonnaroo in 2015: the pop titan is something to behold in concert, and very funny and self-aware, too. So it was an alarming bummer last March when he postponed several shows due to an undisclosed medical condition that required surgery and extensive recovery time.

Those shows ended up being canceled entirely a couple months later and it was made public that the condition was normal pressure hydrocepalus (NPH), which is caused by a buildup of fluid in the brain. Joel hasn't played a full concert since last February.

But he did make a surprise appearance on Friday, January 2nd, with the famed Joel cover band Turnstiles (no, not the hardcore kids, though this one did open for Vampire Weekend a bunch of times) at their Wellington, FL tour stop.

Joel sang and performed on 1978's "Big Shot," and, curiously, 1989's "We Didn't Start the Fire," which is widely reviled even by him (Joel once compared the melody to a dentist drill). But he is ever the consummate professional, and took the stage by telling the crowd, "I wasn't planning on working tonight."

Watch the piano man sing us a song below.