BIG Trouble - Wizard Grimweed Stories Author:Jonathan Allen The second Magician Grimweed story. In this book BIG stands for "babies into giants", a potion, one drop of which makes one particular mouse grow and grow. The author's previous books include "Who's at the Door?", "Mucky Mouse", "One With a Bun", "Big Towel, Little Owl" and "Potion Commotion".