She explains that ten years earlier, her father, Captain Arthur Morstan, disappeared immediately after arriving in London.

Following the letter's instructions, Holmes, Watson, and Mary go to the Lyceum Theatre; there, they meet a coachman who takes them to the house of Major Sholto's son Thaddeus, the anonymous sender of the pearls.

In the ensuing quarrel, Captain Morstan suffered a heart attack and died, striking his head on the treasure box as he fell.

Afraid he would be suspected of murder, Major Sholto buried the body and hid the treasure, leaving out a small gold chaplet studded with twelve pearls.

The brothers tried and failed to catch the intruder; later on, they found a note pinned to the Major's body, which read "The Sign of Four".

Mary Morstan stays downstairs to comfort the housekeeper, while the others rush up to the laboratory door; through the keyhole, they can see Bartholomew Sholto slumped in his chair, with a "fixed and unnatural grin" upon his face.

Borrowing Toby, a trained scent hound, from a naturalist, Holmes traces the pair to a boat landing.

Learning that Small has hired a steam launch named the Aurora, Holmes, with the help of the Baker Street Irregulars and his own disguises, traces the boat to a repair yard.

Some years later, Small learned that Major Sholto and Captain Morstan, who were guards at the convict barracks, had lost money playing cards.

Small arrived too late to hear of the treasure's location, but left the note in the room anyway as revenge for the treatment of himself and the Sikhs.

Sir Arthur Conan Doyle described how he was commissioned to write the story over a dinner with Joseph Marshall Stoddart, managing editor of the American publication Lippincott's Monthly Magazine, at the Langham Hotel in London on 30 August 1889.

The dinner was also attended by Oscar Wilde, who eventually contributed The Picture of Dorian Gray to the July 1890 issue.

It was the short stories, published from 1891 onwards in Strand Magazine, that made household names of Sherlock Holmes and his creator.

The cast included Edward H. Smith as Sherlock Holmes, F. H. Oliver as Dr. Watson, and Viola Karwowska as Mary Morstan.

Adapted by Edith Meiser, the episodes aired from 9 November 1932 to 14 December 1932, with Richard Gordon as Sherlock Holmes and Leigh Lovell as Dr.

[8] On Saturday 2 March 1963, the story was dramatised by Michael Hardwick for the BBC Home Service as part of the 1952–1969 radio series, as a ninety-minute episode on Saturday-Night Theatre, with Carleton Hobbs as Holmes and Norman Shelley as Watson.