Sherlock Holmes is dead. Or so it is assumed. The world knows the great detective went over the falls at Reichenbach with his nemesis Professor Moriarty. But as Holmes' body was never retrieved a number of frauds, fakes, and charlatans have come forward since to lay claim to his identity, and it falls to Dr. Watson to disprove them. Then a telegram arrives informing Watson that three men, each claiming to be Holmes, have been committed to a remote asylum off the coast of Scotland. Now Watson must discover if one of the mad men is the real Sherlock Holmes.