On a dark and stormy night, the kids tell a scary story about local legend Big Bad Ben! Mouse says he doesn't exist, but when a dark figure arrives at the house, they all believe it's Big Bad Ben - even Mouse! Who is this stranger in the storm? Can they work together to protect themselves? And, hang on, didn't Cheese order pizza?

When the kids won't stop being loud, Mouse uses an invention that causes the others to swap voices so they can hear how irritating they sound. At first the kids have fun with each other's voices, using them to playing tricks - but how will Boy get through school when all he can say is ‘meow'?