When Lauren sees a tiny mouse, Nana teaches her a song to sing three times by moonlight to lure him out of the shadows. Avoiding the suspicious eyes of Nana's fat cat Selwyn, Lauren meets the mouse. He is holidaying with his family at Nana's house. When the mice get trapped inside Nana's grandfather clock, Lauren must find a way to free them without Selwyn seeing. Will Monsieur Fromage be able to follow in the pawsteps of his ancestor Sir Hickory Dickory's most famous climb?