The Good Comrades are a collection of varied gentlemen who crave one thing - solitude. They reside at Drearcliff House, ancestral home of their eldest member. All seems serene and convivial until one by one the members begin to perish in the most grisly of manners. Foul play is suspected by the Good Comrades' insurance agent, who turns to Sherlock Holmes and Dr. John Watson for guidance.
Leo, a former convict, is living in seclusion on an island with his step-daughter, the daughter of his late wife. Leo was framed by a group of former business associates, and he also suspects that one of them killed his wife. He has invited the group to his island, tempting them by hinting about a hidden fortune, and he has installed a number of traps and secret passages in his home. He is aided in his efforts by a former cell-mate who holds a grudge against the same persons. When everyone arrives, the atmosphere of mutual suspicion and the thick fog that covers the island promise a tense and hazardous weekend for everyone.
In the early part of this century, Maddelena a teenage Italian girl, is attacked whilst walking in the woods. The attack leaves her mentally scarred and our story flashes forward to the 1940s where Maddelena is still troubled. She disappears one day and her daughter vows to find her.
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.
A mystery writer is intrigued by the tale of notorious criminal Dimitrios Makropolous, whose dead body was found washed up on the shore in Istanbul. He decides to follow the career of Dimitrios around Europe, in order to learn more about the man. Along the way he is joined by the mysterious Mr. Peters, who has his own motivation.
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.
A female bail-bond broker and her partner help an accused embezzler prove his innocence. Having the body of the embezzler's late business partner pop up doesn't help matters.
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.