Bruce Wayne is the masked hero Batman. A criminal raids a chemical plant. His employer tipped the police. Batman arrived and knocked him into a vat of chemicals. The criminal became the Joker. He poisons make-up, hairspray, and deodorant to make a combination of them cause the user to die of laughter. He goes to release laughing gas at a parade through floats but Batman arrives and stops him. Joker kidnaps Vicky Vale and takes her into a tall building.