Sherlock Holmes End Justifies?

Sherlock Holmes is confronted by the greatest fear of law enforcement, the perfect crime. He alone realizes that murder has been committed in a small lakeside village in rural Wales. But even as he begins to amass evidence, he realizes that it is not presentable in court. Local law enforcement officials do not even believe that a crime has been perpetrated. Holmes' deductive powers and creative strategizing are put to their sternest test. The denouement will shock the reader.