The action takes place in Victorian England in the last quarter of the 19th century. 27-year-old amateur detective Sherlock Holmes becomes a bystander to a crime along with Dr. John Watson, a military doctor who has just returned from the war in Afghanistan. During the investigation, Watson, not yet having an apartment in London, settles with Holmes in Mrs. Hudson's «half board», and then takes part in the affairs of his new friend. Watson gives Holmes boxing lessons. Watson himself is an experienced boxer, able to deal with several opponents with his bare hands. In addition, he is an excellent marksman. Considering Holmes a genius, the doctor decides to tell the whole world about his talent and the mysteries he revealed in his stories, where he often embellishes the events («the true story» of which the series presents). Watson is taught to embellish events by the editor-in-chief of the «Morning Chronicle».