With safe Lord Brompton someone steals an old letter from the period of "sins of youth" Lord, now that could seriously damage his career. Summoned to help Sherlock Holmes comes to the conclusion that modern, safe complex, which has a lord, he could only open one skilled in the art as David Ballard. She goes to him, indicating that he knows that he is the perpetrator of the theft, and he was hired by Dr. Sergius, Brompton main opponent in the development of an important treaty for England. Lord is against the adoption of a document unfavorable for the country, Sergius has long tried to persuade him to change the decision. Ballard warns Holmes that when Sergius it takes to get from him a document, you are sure to kill him as an inconvenient witness their machinations. Frightened thief without much resistance gives detective a stolen letter also agrees to write a statement in which he admits to theft. Upon hearing the news that the letter fell into the hands of Holmes, Sergius asks him return of the document, threatening his weapon. The detective meets the demand. Sergius triumphs, but not for long.
—Butterbaugh