Essential Student Texts: The Sign of Four, Paperback/Arthur Conan Doyle

For the past six years, Mary Morstan has received a valuable pearl in the post. After the sixth pearl, an anonymous letter requests a meeting. Is this linked to her father's disappearance or the death of Major Sholto, her father's friend? This edition of Conan Doyle's classic Sherlock Holmes mystery comes with accessible and informative notes.