The Sign of Four is the second Sherlock Holmes novel written by Sir Arthur Conan Doyle. It is gratefully much better than the first novel. Doyle finds his writing grove and a literary hero is born. This is the novel that introduces the audience to many things, including Holmes’s drug use and Watson’s lady love.
Mary Morstan is a young lady who appeals to Holmes and Watson for help with an unusual case. Since her father disappeared several years before, she has received a yearly gift of a pearl. This year, however, she received a letter which urges her to meet with the sender that night. The letter also stipulates that she can bring two non-police friends, so this is where she enlists the help of our heroes. Through the course of the adventure, there is murder, lost treasure, a peg-legged villain, and other mysteries a plenty. It makes for an exciting tale.
The Sherlock stories are always amusing; they’re also relatively short and can be read (or in this case, listened to) quickly.