Batman, after some introductory scenes in which he battles some bad guys with the help of Barbara Gordon as Batgirl, goes to confront The Joker at Arkham Asylum, only to discover he has made his escape and is out and about causing havoc. The Joker, out to prove that anyone can go as mad as he has given the right (or wrong) circumstances ("All it takes is one bad day", so he says), sets about committing some truly heinous acts toward some of the people who are fighting on the side of good. In between the contemporary story scenes, we get flashbacks to Joker's past as a failing comedian who ended up turning to a life of crime in order to support his wife and unborn child, resulting in tragedy that cracks his psyche, and physically transforms his appearance to look as maniacal on the outside as he feels on the inside.