For me, it was a real chore to understand what was going on in the plot, due to a combination of:
1) Not reading the synopsis in the playbill.
2) Most of Billy Joel's lyrics being drowned out by the orchestra
3) Not being a dance connoisseur
Of course, it could just be me.
"Y'know, I think Bertolt Brecht was rolling in his grave."
-Nellie McKay on the 2006 Broadway production of The Threepenny Opera, in which she played Polly Peachum