Tumtum and Nutmeg
Mr and Mrs Nutmouse (respectively: Tumtum and Nutmeg) live in Nutmouse Hall a grand house (for mice) secreted within the broom closet of Rose Cottage. Rose Cottage is the home of a human family: Mr Walter Mildew and his children, Arthur and Lucy. Mr Mildew is an inventor and is struggling to maintain the family while he develops his latest invention, a mechanical mouse that cleans. Due to their father's absent-mindedness and financial situation, Rose Cottage is in poor repair and Arthur and Lucy wear threadbare clothes and are frequently hungry.
Nutmeg begins, with Tumtum's help, to help take care of the children. Using the cover of "Nutmeg, a Fairy of Sorts", Nutmeg cleans the attic in which the children sleep and mends their clothes while Tumtum makes repairs to both the room and the children's toys. The children repay Nutmeg's kindness by leaving treats for them in the doll's house.
Things change when Aunt Ivy comes to stay while her home in Scotland is being fumigated for mice (which she hates). After a chance sighting of Tumtum and Nutmeg, Ivy poisons Tumtum (though not fatally) and makes plans to gas Nutmouse Hall. In desperation Nutmeg enlists the help of General Marchmouse, a recently retired member of the mouse army. Marchmouse, with much unacknowledged help from Nutmeg, formulates a plan to drive Ivy from the house via a massed charge of the village mice.
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