"We imagined what might have happened acted upon the supposition and find ourselves justified. Let us proceed."
? Arthur Conan Doyle The Memoirs of Sherlock Holmes

Could it be that Sherlock Holmes has finally met his match in the villainous Professor Moriarty? Quite possibly. The only way to know for certain is to read the climactic story "The Final Problem" from this collection of Sherlock Holmes tales.

In this second compilation of stories by Sir Arthur Conan Doyle (following The Adventures of Sherlock Holmes) we learn about Holmes' first-ever investigation in "The Gloria Scott"; meet his older smarter (and fatter and lazier) brother Mycroft; and are introduced to the most evil criminal mastermind in English literature Professor Moriarty.