In the midst of World War II, Sherlock Holmes rescues the Swiss inventor of a new bomb-sight from the Gestapo and brings him to England, where he quickly falls into the clutches of the evil Professor Moriarty.
Loursat, a lawyer, lives with his daughter Nicole in a sinister and vast bourgeois residence. Abandoned for nearly twenty years by his wife, the brilliant lawyer has sunk into alcoholism and his relationship with his daughter is virtually non-existent. However, one day the corpse of a stranger is discovered in the residence of Loursat. Nicole, who frequents a gang of young people who escape boredom by stealing cars and other objects, is immediately suspected.
It is prior to the commencement of World War II, and Japan's fiendish Black Dragon Society is hatching an evil plot with the Nazis. They instruct a brilliant scientist, Dr. Melcher, to travel to Japan on a secret mission. There he operates on six Japanese conspirators, transforming them to resemble six American leaders. The actual leaders are murdered and replaced with their likeness.
Topper is once again tormented by a fun-loving spirit. This time, it's Gail Richards, accidentally murdered while vacationing at the home of her wealthy friend, Ann Carrington, the intended victim. With Topper's help, Gail sets out to find her killer with the expected zany results.
In the middle of a pictorial lecture on his recent expedition to the Mongolian Desert, Dr. John Benton,the famous explorer, drinks from the water bottle on his lecture table, collapses and dies. His last words "Eternal Fire" are the only clue Chinese detective Jimmy Wong and Captain Street of the police department have to work on.
Dr. Bernard Adrian is a kindly scientist who seeks to cure a young woman's polio. He needs human spinal fluid to complete the formula for his experimental serum. Meanwhile, a vicious circus ape has broken out of its cage, and is terrorizing the townspeople. Can there be a connection?
American crime reporter John Jones is reassigned to Europe as a foreign correspondent to cover the imminent war. When he walks into the middle of an assassination and stumbles on a spy ring, he seeks help from a beautiful politician’s daughter and an urbane English journalist to uncover the truth.
Shipping magnate Cyrus Wentworth, downcast over a disaster to his ocean liner 'Wentworth Castle' (carrying, oddly enough, an illicit shipment of Chinese bonds) is shot in his office at the very moment of kicking out his daughter's fiance Dick Fleming. Of course, Captain Street arrests Dick, but reporter Bobbie Logan, the attractive thorn in Street's side, is so convinced he's wrong that she enlists the help of detective James Lee Wong to find the real killer.
When a police officer is murdered, Captain Street looks to Mr. Wong to catch the killer. Prime Suspect: Frank Belden Jr., whose father is a businessman well known for both his success and dishonesty. Mr. Wong faces increasing danger and is nearly executed himself as the investigation develops in treachery and complexity. As Mr. Wong follows the trail of dead bodies, he uncovers a jewel smuggling ring on the San Francisco waterfront and a case much larger than the death of a police officer.
Captain Drummond and his girlfriend want to marry but a hidden treasure in the house in which they want to celebrate their marriage is complicating the situation involving a series of deaths and an elusive murderer.
Detective James Lee Wong must find the "Eye of the Daughter of the Moon," a priceless but cursed sapphire stolen in China and smuggled to America. His search takes him into the heart of Chinatown and to the dreaded "House of Hate" to find the deadly gem before it can kill again.
While participating in a contest at a local newspaper in which school children are asked to submit a news story, local attorney Carson Drew's daughter Nancy intercepts a real story assignment. She "covers" the inquest of the death of a woman who was poisoned. Nancy doesn't think the young woman accused of the crime is guilty and corrals her neighbor Ted into searching for a vital piece of evidence and stumbles onto the identity of the real killer.
On a train headed for England a group of travelers is delayed by an avalanche. Holed up in a hotel in a fictional European country, young Iris befriends elderly Miss Froy. When the train resumes, Iris suffers a bout of unconsciousness and wakes to find the old woman has disappeared. The other passengers ominously deny Miss Froy ever existed, so Iris begins to investigate with another traveler and, as the pair sleuth, romantic sparks fly.
A chemical manufacturer is killed just after asking detective James Wong to help him. So detective Wong decides to investigate this as well as two subsequent murders.
Pepe Le Moko is a notorious thief, who escaped from France. Since his escape, Moko has become a resident and leader of the immense Casbah of Algiers. French officials arrive insisting on Pepe's capture are met with unfazed local detectives, led by Inspector Slimane, who are biding their time. Meanwhile, Pepe meets the beautiful Gaby, which arouses the jealousy of Ines.
Although Charlie and Lee are in Monaco for an art exhibit, they become caught up in a feud between rival financiers which involves the Chan's in a web of blackmail and murder.
Lamont Cranston assumes his secret identity as "The Shadow", to break up an attempted robbery at an attorney's office. When the police search the scene, Cranston must assume the identity of the attorney. Before he can leave, a phone call summons the attorney to the home of Delthern, a wealthy client, who wants a new will drawn up. As Cranston meets with him, Delthern is suddenly shot, and Cranston is quickly caught up in a new mystery.