Jeannie

The pregnant wife of the Joker. Despite only making a very brief appearance, it can be argued from information provided in the Killing Joke that Jeannie is one of the most pivotal characters in the Batman series. The most commonly cited backstory to the Joker is in the Killing Joke, which depicts him as originally being an engineer at a chemical plant who quits his job to become a stand-up comedian, only to fail miserably. As a result, he lives in a run-down apartment where the ceilings are strung with laundry and their view is of a brick wall. He’s an unsuccessful stand-up comic who is very worried about how he will provide for his family. Nevertheless, Jeannie remains optimistic, reassuring him that they will find a way and laughs at one of his jokes.

Desperate to support his wife and unborn child, the man agrees to help two criminals break into the chemical plant where he was formerly employed. However, Jeannie soon finds out and manages to convince her husband at the last minute to back out of the plan. Unfortunately, just as the man was meeting with the criminals, the police contact and inform him that Jeannie and their unborn child, which the man had ardently proclaimed to be a baby boy after he presented his wife with a baseball glove as an early gift, have died in a household accident.

Stricken with grief and shock, the man attempts to back out of the plan, but the criminals strong-arm him into keeping his promise. As soon as they enter the plant, however, they are immediately caught by security and a shoot-out ensues, in which the two criminals are killed. As the engineer tries to escape, he is confronted by Batman, who is investigating the disturbance. Terrified, the engineer leaps over a rail and plummets into a vat of chemicals. When he surfaces in the nearby reservoir, he removes the hood and sees his reflection: bleached chalk-white skin, ruby-red lips, and green hair. These events, coupled with his other misfortunes that day, drive the engineer completely insane, resulting in the birth of the Joker.

If the information provided by the Joker is be considered canon or even true, then it is the deaths of Jeannie and their unborn child which essentially drives the man to insanity. Later in Batman: Gotham Knights #54, the Riddler approaches the Joker for protection against Hush by stating that he witnessed a corrupt police officer, Oliver Hammet, set the fire that resulted in Jeannie's death. Now armed with the name of the person who killed his wife and unborn child, the Joker wants nothing more than to find the man and kill him.