The Valley of Fear by Sir Arthur Conan Doyle is really two stories, loosely linked by several characters. The first story regards the murder which occurs in a moated manor house in a quiet country area in England.
Sherlock Holmes does his usual thing and investigates and solves the mystery surrounding this murder, with the assistance of Dr Watson. To be completely honest, there wasn’t much to this part of the story at all. I guessed at how it all happened and was fairly close to working it out without Sherlock having to tell me. My powers of deduction obviously work.
The second story is set in the American mining town where the owner of the English manor previously lived. The Valley of Fear is an apt name for the mining town and surrounding area which was ruled by a wicked set of men known as Scowrers, who become rich and powerful through blackmail, violence and murder. Sherlock Holmes and Dr Watson do not feature at all in this story, which precedes the English murder.
I found this part of the story fascinating. The Scowrers, who call themselves Freemasons, are merciless and the control they had over The Valley of Fear is almost total. Again, I guessed at how it would all unfold and my deductions were correct, but that did not detract from my enjoyment of the story at all.
If you are looking for a Sherlock Holmes story where you will be too terrified to sleep, read The Hound of the Baskervilles instead of The Valley of Fear. But if you enjoy Sherlock Holmes at work, read the story and as for the prequel, or whatever the American bit of this book is called, take it as an enjoyable bonus.