Mortimer Brewster, a newspaper drama critic, playwright, and author known for his diatribes against marriage, suddenly falls in love and gets married; but when he makes a quick trip home to tell his two maiden aunts, he finds out his aunts' hobby - killing lonely old men and burying them in the cellar!
The famous Borgia Pearl, a valuable gem with a history of bringing murder and misfortune to its owner since the days of the Borgias, is brought to London, thanks in part to Sherlock Holmes. But before long the jewel is stolen, due to an error on Holmes' part, and shortly thereafter, a series of horrible murders begin, the murderer leaving his victims with their spines snapped and surrounded by a mass of smashed china.
When a woman is found dead with her throat torn out, the local villagers blame a supernatural monster. But Sherlock Holmes, who gets drawn into the case from nearby Quebec, suspects a human murderer.
When a treasure hunter seeks a downed airplane in the jungles of Africa, he encounters one of the passenger's young daughter, now fully grown, and with a gorilla protector.
Sherlock Holmes investigates a series of so-called "pajama suicides". He knows the female villain behind them is as cunning as Moriarty and as venomous as a spider. Based on "The Sign of Four" and the short stories "The Dying Detective", "The Final Problem", "The Speckled Band" and "The Adventure of the Devil's Foot".
During WWII several murders occur at a convalescent home where Dr. Watson has volunteered his services. He summons Holmes for help and the master detective proceeds to solve the crime from a long list of suspects including the owners of the home, the staff and the patients recovering there.
One dark and stormy night, an escaped convict, an embezzler, a runaway daughter, her intended and her father, and a gangster take refuge in a remote inn called "The Black Raven" after the nickname of a second gangster who owns it; and murder ensues.
In the small town of Crownport local attorney Bill Adams is trying to break up the ring of corrupt town officials by running for mayor. The cards seemed stacked against him when he gets help from a visiting hunter who, unknown to Adams and the rest of the town, is actually vacationing supreme court justice John Josephus Grant.