One of the most keen and intricate cases, Sherlock Holmes was ever involved into, but even now he managed to rise to the occasion. This is a political and spy story, together with a detective plot: A body of a young clerk, possessing secret drawings of an up to date submarine, was found on railway lines of London tube. But the most awful is the fact that the important part of the drawings disappeared without leaving any trace.
The author of the book, Sir Arthur Ignatius Conan Doyle, one of the famous founders of the detective genre, hardly needs to be introduced, being a prolific writer of the 19th-20th centuries, whose other works include science fiction stories, historical novels, plays and romances, poetry, and non-fiction.
The book can be a wonderful introduction to the larger body of Holmes stories, as well as a delightful read for any mystery lover.