Scientist Mr. Echidna exclusively studies Muroidea, or more commonly known as rodents. Using the method of "gene breeding", he was able to breed a mouse with super genes named NiuNiu.

An evil mouse, Yizhier, found out about NiuNiu and kidnapped her, infecting her with a virus called ZSN.

Fortunately, the sheriff and city guard, Dalmatian, a black cat, started to sneak into Yizhier's mouse cave to confront Yizhier head on...