Charles Augustus Milverton

Holmes is hired by the débutante Lady Eva Blackwell to retrieve compromising letters from a blackmailer. The blackmailer demands £7,000 for the letters, which would cause a scandal that would end Lady Eva's marriage engagement. Holmes visits Milverton's Hampstead house disguised as a plumber to learn the plan of the house. He cultivates the acquaintance of his housemaid and even becomes engaged to her. Holmes tells Watson that he has a hated rival who will step in when the plumber disappears.