Extortion

The plot of the film "The King of Blackmail" is based on Arthur Conan Doyle's short story "The Adventure of Charles Augustus Milverton" and revolves around compromising letters - correspondences of married women with their lovers. The legal theme of the film concerns the criminal activities of Charles Milverton, who, by purchasing compromising letters about aristocrats, would demand payment from his victims. In most cases, he received the money as the victims preferred not to go to the police either for ethical reasons or out of fear of losing their social reputation.
In this film episode, Mycroft explains to Sherlock the circumstances of Lady Eva Brackwell's case. He mentions that Lady Eva has an upcoming wedding which might not take place due to compromising letters addressed to a certain esquire that fell into Milverton's hands (played by actor Boris Ryzhukhin). The only way to fulfill Lady Brackwell's request is to burglarize Milverton's mansion and destroy all the compromising letters.
In the presented shot, Sherlock Holmes and Dr. Watson find themselves in Charles Milverton's study and become unwilling witnesses to his murder by the widow of Lord Huxley, a role brilliantly performed by actress Valentina Panina. After Lady Huxley has left the crime scene, Holmes and Watson throw all the letters stored in the study into the fireplace and leave.
The issue of bringing the blackmailer to responsibility in the Victorian era involved not only ethical but also legal aspects. Only certain forms of extortion ("blackmail") were covered by the Libel Act 1843 and the Larceny Act 1861, as well as common law precedents from 1707 (R v. Woodward) and 1805 (R v. Southerton), and were classified as serious crimes. Not all monetary demands qualified as criminal acts. Under late 19th century English law, Milverton's blackmail could have been classified as a less serious offense bordering on an administrative violation.
In the film's conclusion, Inspector Lestrade asks Sherlock to assist with the Milverton murder case, but the detective refuses to investigate this murder. The film "The King of Blackmail" became the first in a trilogy about combating the criminal community.