10 Comic Book Villains Whose Origins Are A Mystery
1. Joker
The Joker was created by Bill Finger and Jerry Robinson and premiered in Batman #1 in 1940. He was initially supposed to be a one-off spree killer that was to die at the end of the issue. DC editor Whitney Ellsworth decided the Clown Prince was too good a character to let slip away and he was saved in a single panel added to the end.
There has never been a definitive origin story for the Joker. No one knows his real name or where he is from. In the first origin story from Detective Comics #168, the unnamed man was the villain known as the Red Hood. A robbery of the Monarch Playing Card company went bad when Batman arrived and the Hood was dropped in a vat of chemicals that bleached his skin, colored his hair green and his lips bright red. This unhinged the man and he took the name the Joker as his nom de crime.
Future origins add to this first one. Alan Moore’s The Killing Joke claimed he was a former engineer who quit to become a stand-up comedian, and a group of thugs forced him into the Red Hood persona. In two different retellings, the writers have given him the name “Jack” in a possible homage to Jack Nicholson's Joker from the first Tim Burton Batman film.