While vacationing in St. Moritz, a British couple receive a clue to an imminent assassination attempt, only to learn that their daughter has been kidnapped to keep them quiet.
When the Ranger Sergeant returns murdered with a note that LaFarge did it, Trooper Burke sets out to after LaFarge. Working undercover, he saves LaFarge's life and this gets him into LaFarge's gang. He then arrests LaFarge and brings him in only to learn that LaFarge is not only innocent but is now a prisoner of the real killer.
A valuable gem from India is stolen in an old dark mansion and it is up to Scotland Yard inspector Charles Irwin to find out who did it among all the suspects who were in the house.
The owner of a large mansion in the country throws a costume party for some of his friends. However, the party turns sour when he is found stabbed to death in a closet. The police and a guest try to discover who committed the murder.
When a radio star is found murdered in her home, everyone assumes that the mysterious young woman discovered with her is the culprit — everyone, that is, but newspaper reporter Jerry Beall, who sets out to prove her innocence.
Eight people are invited by an unsigned telegram to a penthouse apartment, where they find themselves locked in and greeted by their unknown host's voice via the radio, who explains that before the night is over each one will be die unless they manage to outwit the ninth guest, Death.
A popular young student finds herself accused of a series of murders that have occurred on the college campus. Her boyfriend, a reporter for the local newspaper, knows she didn't do it, and and sets out to prove her innocence and catch the real killer.
Philo Vance, accompanied by his prize-losing Scottish terrier, investigates the locked-room murder of a prominent and much-hated collector whose broken Chinese vase provides an important clue.
A night of love, intrigue, death and blackmail leaves stage-star Elise Manning's fate at stake in a conflict with the unscrupulous Doctor Gruell. A rejected lover dies in Miss Manning's apartment, and Gurell implies that the death was murder and attempts to blackmail the actress. The climax brings the actress, her fiancé and the dead-man's wife face-to-face in an emotional denouement.
An elderly detective sets out to find who murdered a lecherous stage actor. His estranged wife? His would-be fiancee? Her father? Her boyfriend? A suicided actress's sister? The temperamental prop man? Or maybe the show's talented female chimpanzee?
British Egyptologist, Professor Morlant, seeks immortality through the power of a jewel buried in the tomb of an Oriental idol. Upon his death, Morlant returns to earth to seek vengeance upon those who removed the jewel from his grave.
Rival newspaper reporters Pat Morgan and Ted Rand find themselves unraveling the mystery behind the death of a millionaire philanthropist who fell from his penthouse balcony. When it is discovered that the plunge was not an accident, the building's residents come under suspicion. Soon, the body count begins to mount as three more murders occur by strangulation.
A man known to be a mute is suspected of committing a murder, as he was noticed at the scene. However, witnesses saw and heard him talking as he was leaving the scene of the crime. The police must determine if he is the actual killer or if he is being framed.
In London, a secret society led by lawyer Thaddeus Merrydew collects the assets of any of its deceased members and divides them among the remaining members. Society members start dropping like flies. Sherlock Holmes is approached by member James Murphy's widow, who is miffed at being left penniless by her husband. When Captain Pyke is shot, Holmes keys in on his mysterious Chinese widow as well as the shady Merrydew. Other members keep dying: Malcom Dearing first, then Mr. Baker. There is also an attempt on the life of young Eileen Forrester, who became a reluctant society member upon the death of her father. Holmes' uncanny observations and insights are put to the test.
The heirs to a family fortune are required to attend a seance at the spooky old family mansion. However, throughout the night members of the family are being killed off one by one.
A mysterious criminal known as The Whispering Shadow commits crimes by means of a gang he controls by television and radio rays. Jack Norton, whose brother was murdered by The Whispering Shadow, suspects that the eerie Professor Strang - whose ghostly wax museum contains figures far too lifelike - may be involved in the crimes.