Thomas Jackson was the assistant director of Gotham City's bureau of copyrights. After Joker failed to pressure director G. Carl Francis into cooperating failed, Joker set his sights on Thomas Jackson. The police and Batman stepped into help him. Batman dressed up as Jackson, while Jackson dressed up as Batman. But Joker's plan succeeded. He used Jackson's own cat. Jackson's cat was infected with Joker venom and attacked its master (possible by scent since Jackson was dressed like Batman). Jackson was infected and Batman administered the antidote, but it was too late an Jackson died.