9 Storylines That Defined Popular Comic Book Characters

The Joker is a character who has thrived off of his anonymity, as his lack of a backstory is what makes the villain so compelling. He could be anyone, both in the sense that his identity has slipped through the cracks of society, and that it's just so easy for someone to plunge off of the deep end. So easy, the Joker says, that all it takes is "one bad day".

The Killing Joke gives the 'Clown Prince of Crime' his backstory while also acknowledging that it probably isn't true, and should just be added to the dozens of other potential lives that could have led to the man behind the makeup. It doesn't even matter if it is true because that's not the point of the story. Instead, it's a glimpse into the fractured psyche and not of his past.

The Joker may have had his one bad day, or he could have simply risen from the depths of a universe requiring an equal chaotic force to oppose the order that is the Batman. Though the Joker does not manage to break James Gordon, he may have broken the Bat. This story cements the Joker as the best villain of all time, for the mere act of asking if everything someone has can go up in flame in the span of a day - even their sanity.