A few years after this disappearance an advertisement appeared in a paper asking for Miss Morstan to reveal her address. Upon the advice of her employer she did so and that same day she received a valuable pearl in the post. Since then she has received one pearl a year for the last six years.
Miss Morstan has now received a letter which urges her to meet with the sender that night. The anonymous sender permits her to bring two friends as long as they are not police. Later that night on their way to the rendezvous Miss Morstan tells Holmes that Sholto and her father were in charge of the convict guard at the Andaman Islands. She also shows Holmes a strange paper which was found among her father’s things after he disappeared, the document appears to be a map and a sign with four crosses in a straight line with touching arms is present in the corner. Written below the sign are the words “The Sign of Four” along with three Indian names and one English name.
Holmes discovers that Major Sholto died about six years previously, within a week of the date of his passing Miss Morstan received her first pearl. This fact suggests that Sholto’s heir knows how Captain Morstan died and wishes to make reparation to Miss Morstan.
Upon reaching the rendezvous Holmes, Watson and Miss Morstan are met by a coachman and conveyed to the home of Thaddeus Sholto. Thaddeus and his twin brother Bartholomew are the only children of the deceased Major Sholto who eleven years previously had returned to England in possession of great wealth and settled in Upper Norwood. Thaddeus relates that his father was fearful of his personal safety and also seemed to have an aversion to men with wooden legs.