Igor Maslennikov

At the Kremlin's behest, Bulgarian secret services, along with Polish comrades, prepare for an attempt on the Pope's life. The best candidate to cover up the tracks and eliminate the assassin is retired SB agent Konstanty Brusicki, nicknamed 'Bruno', who has only one month left to live.

A girl named Mary Morsten comes to Sherlock Holmes, who asks him and the doctor to help solve the annual receipt of one pearl by her parcel and in the search for her father, who disappeared many years ago. Holmes and Watson do not refuse her help and find out that Miss Mary is the heiress of a huge fortune — the treasures of Agra, which are also claimed by the sons of Major Sholto and Jonathan Small — an escaped convict with a wooden prosthesis instead of a leg, whom the elder Morsten and Sholto deceived (while Sholto also deceived Morsten).

After upsetting the criminal underground in 'the Master Blackmailer' case, Sherlock Holmes has to face his archenemy: Prof. Moriarty.

Dr. Watson, who served in the English armed forces and was in the Afghan war, retires and returns to his homeland, in England. Since the financial situation of the doctor is very precarious, his long-time friend Mr. Stamford offers him to rent a room in the house at 221-B Baker Street, which is rented by an elderly lady - Mrs. Hudson. The second rented room is already occupied by another gentleman - the mysterious Mr. Sherlock Holmes. Holmes makes an ambiguous impression on Watson. He conducts complex chemical experiments with blood, plays the violin, has the deepest knowledge about cigar ash, London dirt and criminal law, but at the same time demonstrates complete ignorance of well-known truths (for example, the fact that the Earth revolves around the Sun), does not read fiction, as well as books on history and philosophy. At the same time, very strange visitors constantly come to Holmes, and on the table he has portraits of personalities of a disgusting appearance.

The second part of the Soviet TV adaption.

Holmes and Dr. Watson help a young lady who is receiving anonymous letters 10 years after her father passed away under shady circumstances. They find themselves in an enigma involving a treasure, murder and a love interest for Watson.

During the investigation of the Agra treasure case, Holmes and Watson recall another case that Holmes had investigated earlier. The King of Bohemia comes to Holmes under a false name, who behaves somewhat arrogantly at first, and then plaintively asks for help.

This film version was released before the premiere of the full two-part television version (The Adventures of Sherlock Holmes and Dr. Watson: The Twentieth Century Approaches). In this version the entire plot of the story Bruce-Partington Drawings was deleted.