Holmes and Watson board a passenger train bound from London to Edinburgh, to guard the Star of Rhodesia, an enormous diamond worth a fortune belonging to an elderly woman of wealth; but within the first hour of the trip, the woman's son is murdered and the diamond stolen and any of the passengers in their car could be the killer thief.

A convicted thief in Dartmoor prison hides the location of the stolen Bank of England printing plates inside three music boxes. When the innocent purchasers of the boxes start to be murdered, Holmes and Watson investigate.

Bedelia Carrington is living happily, it appears, in Monte Carlo with her husband Charlie Carrington. But a cultivated young artist, Ben Chaney, begins probing into her past with curious concern. Chaney, who is really a detective, learns that Bedelia's obsession for money has led her, in the past, to husband-poisoning for the insurance money.

A beautiful but unscrupulous female performer manipulates all the men in her life in order to achieve her aims.

The dream is unusually vivid: Bank employee Vince Grayson finds himself murdering a man in a sinister octagonal-shaped room lined with mirrors while a mysterious woman breaks into a safe. It is so vivid that Vince suspects it may have really happened. To get the dream off his mind, he goes on a picnic with some relatives. When a thunderstorm forces his party into a nearby mansion, Vince discovers that the bizarre room does exist, and it means nothing but trouble.

An old man and his sister are concealing a terrible secret from their adopted teen daughter, concerning a hidden abandoned farmhouse, located deep in the woods.

An adolescent believes that his widowed mother's suitor may have murdered his father.

Ronnie Jackson is a lowly baby photographer who secretly fantasizes about being a private detective. When a lovely baroness actually mistakes him for one and asks him to help locate her missing husband, Baron Montay, Ronnie finds himself agreeing. Several days later he is on death row whiling away the hours until his execution by recounting to a group of reporters the bizarre tale of how he ended up there.

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.

A theatre critic teams up with a cop to investigate the murder of a Broadway actor.

A gang of criminals, which includes a piano player and an imposing former convict known as 'Gruesome', has found out about a scientist's secret formula for a gas that temporarily paralyzes anyone who breathes it. When Gruesome accidentally inhales some of the gas and passes out, the police think he is dead and take him to the morgue, where he later revives and escapes. This puzzling incident attracts the interest of Dick Tracy, and when the criminals later use the gas to rob a bank, Tracy realizes that he must devote his entire attention to stopping them.

Two reporters search for a missing body in a wax museum.

An estranged wife shows up after a nearly 7 years of disappearance -- thought to be dead, to prevent her husband from marrying his new love until someone kills her.

A woman is married to the son of a doctor, the proprietor of a private sanatorium, where she is under unwilling treatment. Both the son and the doctor indicate they want the marriage dissolved. Arriving at the scene is a mysterious personage identified as the doctor's brother who formerly was a stage magician in Europe. He is accompanied by a threatening dwarf...

Detective Tracy rescues Tess Trueheart and Junior from a killer called Splitface.

A feud between rival newspapermen Kruger (Bromberg) and McDonald (Guilfoyle) goes deadly when blackmailing McDonald ends up murdered and his corpse planted in the trunk of Kruger's car. Good guy Kruger attempts to hide McDonald's body, with the help of chauffeur Hogan (Jenks), to keep from being charged with murder. However, zany scenarios occur as the body just won't stay hidden, and keeps on popping up in multiple places where Kruger is located, leading to him hiding the body again and again while Kruger tries to find the real killer.

A meek reporter happens upon a murder, an escaped gangster and a stolen jade chess set.

Susan Hart, assistant to private detective Russ Ashton, is given a camera concealed in a hat box and assigned to take a picture of a woman. A gun is accidentally hidden in the box and the woman is killed. Susan is charged with murder, but Russ and his less-than-useful associate, Harvard, get on the case.

An insurance salesman, Albert Tuttle, is hired as a body guard for a millionaire.

A wealthy man hires a detective to investigate his wife's mysterious past.

A crooked real estate tycoon tricks a trusting young woman out of her small candy store. When he is found dead, the girl is suspected of the crime.

An architect (Chick Chandler) studies the doors of six shops and an apartment house to solve a gem theft/double murder.

John Calvert takes over as the Falcon in this Poverty-Row continuation of the film series.

Both the Range Buster and Rance and his outlaw gang are looking for stolen gold bullion. To scare people away from the ranch where the gold is hidden, Rance has his man imitating ghosts. The gold is in a steel cased organ but a certain combination of organ stops need to be pulled to obtain the gold.

A young woman, a trio of singers, and a mystery writer are among the guests at a house long-considered to be haunted.

Convinced that she has what it takes to be a detective, inquisitive secretary Kitty O'Day gets her chance to put her sleuthing skills to the test when her investment broker boss is mysteriously murdered. But Kitty's investigation hits a snag when Inspector Miles Clancy begins to suspect that she's the culprit.

Reporter Patsy Reynolds and photographer Eddie Porter are assigned to interview John Foster, head of the Emmerson Foundation regarding a listening device the organization is working on. Foster evades them and they to the lab to see Professor Reynolds, the real inventor. Soon, they are involved in several shootings, blueprints that change hands several times, a corpse in their car that appears and disappears a few times, the loss of their jobs and several people who either think they are killers or candidates for being killed.

Secret Service agents make a deal with a counterfeiting inmate to be released on early parole if he will help them recover some bogus moneymaking plates, but he plans to double-cross them.

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.

After surviving a murder attempt, an auto magnate goes into hiding so his wife can pay for the crime.