Valley of Fear

Sherlock Holmes receives a coded message from an informant in Professor Moriarty's circle

Sherlock Holmes receives a coded message from an informant from Professor Moriarty's background. But the warning comes too late. The owner of the house, John Douglas, is found shot dead on the country estate of Birlstone. Holmes and Dr Watson embark on an investigation that uncovers a series of strange clues and hints of an old enmity that Douglas has been hiding from for years.
Gradually, it becomes clear that the roots of the crime go deep into the past and lead to the American mining region known as the "Valley of Fear". It was there that a once-secret agent of the Pinkerton Detective Service infiltrated a brutal criminal conspiracy that ruled the local mines through extortion, violence and murder.
Sir Arthur Conan Doyle's fourth and final Sherlock Holmes novel has an unusual two-part structure: offers a thrilling tale from the American underworld alongside a classic detective investigation.