What is the joker s origin story in the batman?

Batman: The Killing Joke, a 1988 DC Comics graphic novel by Alan Moore and Brian Bolland, presents the Joker's origin as a tragic backstory. The narrative frames the Joker as a family man and struggling comedian who suffers a severe accident involving chemicals in a vat, which leaves him disfigured and drives him to violence. This origin is depicted through a flashback within the story, which simultaneously shows his attempt to drive Commissioner Gordon insane and Batman's efforts to stop him. The graphic novel loosely adapts the 1951 Batman story 'The Man Behind the Red Hood!' by co-creator Bill Finger, offering a psychological interpretation of the Joker's descent into chaos. Moore and Bolland intended this origin to humanize the villain, portraying him as a product of circumstance rather than inherent evil, though the story remains controversial for its ambiguous moral stance.