Holmes connects a missing teacher and a past mystery when a duke's son is kidnapped. With Jenny Seagrove. A murder investigation leads Holmes and Watson on a wild goose chase. A prowler frightens a scientist's daughter. More repulsive and venomous than any snake is the king of blackmailers.
Thugs steal a manuscript of a biography finished shortly before the death of the man.
Holmes suspects foul play after a man collapses and dies of a strange fever. Inspector Hopkins calls on Holmes to help solve the murder of young Willoughby Smith.