This charming chapter book introduces Tumtum and Nutmeg Nutmouse, who live a secret life in the broom cupboard of Rose Cottage. They become the unseen guardians of the Mildew children, Arthur and Lucy, whose inventor father struggles financially. Nutmeg, posing as a 'Fairy of Sorts,' mends clothes and cleans, while Tumtum makes repairs. The children, in turn, leave treats for their mysterious helpers. The story takes a suspenseful turn with the arrival of Aunt Ivy, a formidable and mouse-phobic relative who discovers the mice and plots their demise, leading Tumtum and Nutmeg to enlist the help of a retired mouse general. It's a heartwarming tale of kindness, resilience, and courage, suitable for ages 4-11, exploring themes of family, empathy, and overcoming adversity.