Gotham City: dark, dangerous, 'protected' only by a mostly corrupt police department. Despite the best efforts of D.A. Harvey Dent and police commissioner Jim Gordon, the city becomes increasingly unsafe...until a Dark Knight arises. Jack Napier, one-time enforcer for Boss Grissom, horribly disfigured after a firefight in a chemical factory...who, devoid of the last vestiges of sanity, seizes control of Gotham's underworld as the psychotic, unpredictable Clown Prince of Crime...the Joker.