Charlotte is a wealthy 19 year old Rhodesian heiress, accompanied to London on the death of her parents by an older, more mature Englishman named Stephen Darnley, a friend of the family. He's a decorated war hero and a thoroughly decent chap.
At least that's what he'd have you believe. Stephen has his eyes on naïve, impressionable Charlotte for one reason only...her money. After a long voyage back to England he proposes to her and is happily accepted. They are married and from then on Stephen wages psychological war against his young, innocent wife.
He employs a vicious older harridan of a woman, Miss Francis, as a housekeeper in their smart London house and insists that Charlotte learn the rudiments of how to manage a house. But rather than learn the technical aspects as she first assumed, Charlotte is thrust into the life of an actual maid, a skivvy under Miss Francis's iron hand and implacable will.
She learns first hand about the difficulty of running a large house and any perceived "slacking" or "laziness" results in corporal punishment, often Miss Francis's lithe Malacca cane or more usually the calloused palm of her hand applied to Charlotte's bare bottom or the backs of her slim thighs.
When she's not working, Stephen makes her wear juvenile, shameful clothes in order to keep her in her place as he likes to describe it. The overall effect is that his 19 year old wife appears to be his strictly disciplined daughter rather than his wife.
The plot thickens when a new maid, Mary, is employed and Charlotte is moved into the schoolroom to be taught how to be a good wife for her husband. Once again with the aid of Miss Francis and her cane.