A young woman turns to Sherlock Holmes for protection when she’s menaced by an escaped killer seeking missing treasure. However, when the woman is kidnapped, Holmes and Watson must penetrate the city’s criminal underworld to find her.
Holmes, retired to Sussex, is drawn into a last case when.arch enemy Moriarty arranges with an American gang to kill one John Douglas, a country gentleman with a mysterious past. Holmes’ methods baffle Watson and Lestrade, but his results astonish them. In a long flashback, the victim’s wife tells the story of the sinister Vermissa Valley.