See The Movie That Created The Joker!
"I would be torn on whether or not I should remove it from the deck."
Jerry Robinson first found inspiration for the Joker from a deck of playing cards, but something was missing. According to legend, Robinson found something interesting in watching Bill Finger's 1928 film, The Man Who Laughs. Here's a plot summary below...
Gwynplaine, son of Lord Clancharlie, has a permanent smile carved on his face by the King, in revenge for Gwynplaine's father's treachery. Gwynplaine is adopted by a travelling showman and becomes a popular idol. He falls in love with the blind Dea. The king dies, and his evil jester tries to destroy or corrupt Gwynplaine.
Gwynplaine, played by actor Conrad Veidt, was just what the writers of Batman were looking for. With his carved in smile and malicious look, he was the ultimate inspiration for The Joker and dare I say a big part of the gaping wounds on the sides of Heath Ledgers face in The Dark Knight.
I put the first and second parts below. I would put all 11 parts, but your browser would hate me. So I suggest streaming the first, then when you get to the second part go ahead and load up the third above it to maximize efficiency!