The Adventure of the Copper Beeches

Violet Hunter consults Holmes after being offered a governess job subject to a number of unusual conditions, including cutting her hair short. The wage is extremely high, £120, and she decides to accept the job, though Holmes tells her to contact him if she needs to. After a number of strange occurrences, including the discovery of a sealed-off wing of the house, she does so. Holmes discovers that someone had been kept prisoner in the wing, but when Holmes, Watson and Hunter enter, it is empty. They are accused of freeing the prisoner, who was the daughter of Hunter's employer, who sets his dog on them ?