Batman deals with an arsonist known as Firefly and problems involving Gotham's mayor.

A mysterious villain known as the Riddler challenges Yin, secretly helped by Batman, to a number of riddles. Things are not what they seem from the riddles...

Penguin discovers a sonic device that allows him to turn Man-Bat into his personal slave. Meanwhile, Alfred must deal with a raccoon which has found its way into the Bat-Cave and is wreaking havoc on the electric equipment.