These short stories are the very last ones written by Arthur Conan Doyle about his much-loved fictional detective. Holmes and Watson are faced with cases that range from the suspicious to the seemingly supernatural, and they encounter characters as diverse as an evil Austrian adventurer, a formidable female criminal, a distinguished professor who is acting oddly and a mysterious tenant who refuses to show her face.

In this tale drawn from the note books of Dr Watson, the deadly hand of Professor Moriarty once more reaches out to commit a vile and ingenious crime. However, a mole in Moriarty’s frightening criminal organisation alerts Sherlock Holmes of the evil deed by means of a cipher.