"The Threepenny Opera" is an incredible story written to be an accessible critique of capitalism for the working class.
"You are about to hear an opera for beggars. Since this opera was intended to be as splendid as only beggars can imagine, and yet cheap enough for beggars to be able to watch, it is called the Threepenny Opera."
And it's #publicdomain today!
Which also means the song and character known as Mack the Knife enters the public domain today!