The Joker is a homicidal maniac and the archenemy of Batman. Originally being an engineer at a chemical plant, he quit his job to pursue his dream of being a stand-up comedian, only to fail miserably. Desperate to support his pregnant wife, Jeannie, the man agreed to help two criminals break into the plant where he was formerly employed. He was then confronted by Batman, and tumbled into a vat of toxic chemicals. When he surfaced in the nearby reservoir, and saw his face, he burst into laughter.