Explain the mystery that Jabez Wilson wants Sherlock Holmes to solve.
Jabez Wilson is upset because he has just received notice that the Red-Headed League has been disbanded. He was being employed there because his exceptionally brilliant red hair supposedly made him the ideal candidate for membership in what was represented as a sort of fraternal organization founded by a wealthy man for the purpose of benefiting red-headed men. Wilson was getting generously paid for simply copying articles from the Encyclopedia Britannica. He is apparently hoping that Sherlock Holmes could find out why the League had been disbanded without advance notice and whether it might reopen again, or whether it has moved to a different location. He hates losing that easy income for such simple work. Holmes was sufficiently interested in this seemingly trivial case to go around with Watson to take a look at the shop. He realizes that Wilson's employee is tunneling into a bank vault and was using the Red-Headed League to get Wilson out of the way while he worked on his tunnel. The fact that the League has been disbanded tells Holmes that the burglars are ready to break into the vault. This story is one of Doyle's most popular Sherlock Holmes tales, although it is hard to believe that Wilson would bring his problem to Sherlock Holmes and hard to understand what Wilson thought could be done to help him recover his cushy job.
In "The Red-Headed League," Jabez Wilson is a befuddled client who comes to see Holmes because he cannot understand why a sinecure job that was suggested to him by his recently hired assistant has mysteriously been terminated.
Wilson is a pawnbroker whose business has been none too good, so when "Vincent Spaulding," the assistant, calls his attention to the supposed Red-Headed League and its golden opportunity to earn £4 a week by copying sections from the Encyclopedia Brittanica, he is elated. Yet after a short period of time, he is equally deflated to find a notice on the door of the office to which he has been reporting telling him that "the Red-Headed League is dissolved"—and nothing more.
Being determined not to lose such a good thing without a struggle, he asks Holmes for help. Unlike Mr. Wilson, however, Holmes and Watson are not deceived for a minute by the obvious ploy of using their client's vivid red hair to create a red-herring.