A criminal named Harry "Lightfingers" Hale breaks into Science Hall in Gotham City, and steals a microfilm containing the blueprint of a secret formula compound from a criminal scientist named Professor Dodge. Dodge labors to recover the formula and runs across Batman. Initially, Batman suspects Dodge of stealing the microfilm, but soon learns the truth concerning Lightfingers. He pursues Lightfingers to a futuristic community known as Mechanical City – a town run by robots. Professor Dodge and his cronies take control of the city's automated command center but are unable to capture Harry Hale. Harry manages to hide the stolen microfilm inside one of the robots. Batman deduces the microfilm’s secret location and manages to apprehend members of both Dodge and Harry's gang.