Sherlock Holmes is investigating a series of crimes across Europe that are believed to be connected to criminal mastermind Professor Moriarty. As Holmes and his partner Dr. Watson battle Moriarty's men, they uncover his plan to start a war and make a profit. Holmes ultimately defeats Moriarty, but survives and leaves a question mark on Watson's typewriter.

The continuation of the Sherlock Holmes story.

Sherlock Holmes and Watson must stop a nemesis from executing a plot that puts all of England in danger. As they engage in a battle of wits and brawn, the duo unravels a series of mysteries and uncovers a dark conspiracy.