Cosmo Jones, a correspondence-school detective from a small town, comes to the big city to offer his services to the police. He happens by where a gangster is killed by an opposing gang. Socialite Phyllis Blake is running around with gang member Tom and the opposing gang plan on kidnapping her. Cosmo is with Sergeant Flanagan when the attempt is made in front of a night club, where a bystander is seriously wounded in the gun-battle. Police Chief Murphy blames Flanagan for the shooting and demotes him. Cosmo, with the aid of a porter, Eustace and Flanagan's fiancée, Susan, tries to find the killer. Phyllis is finally kidnapped and Cosmo decides the act was committed by one of the two gangs. He has her father place an ad in the newspaper that contact has been made with the kidnappers. Each gang thinks the other is pulling a double cross, and one gang wipes out the other.
A woman on the run from her abusive husband encounters a mysterious hitch-hiker.
After FBI agent Frank Lacrosse believes his son was kidnapped by a notorious serial killer, he travels to Amarillo, Texas, where he believes the murderer is in hiding. Although officially taken off the case because of its personal significance to him, Frank continues to pursue the killer, causing concern for local sheriff Buck Olmstead. When another victim pops up at a nearby car garage, Frank knows that he is as close as he'll ever be to tracking down the elusive killer.
Mary Henry ends up the sole survivor of a fatal car accident through mysterious circumstances. Trying to put the incident behind her, she moves to Utah and takes a job as a church organist. But her fresh start is interrupted by visions of a fiendish man. As the visions begin to occur more frequently, Mary finds herself drawn to the deserted carnival on the outskirts of town. The strangely alluring carnival may hold the secret to her tragic past.
One evening, Hammer gives a ride to Christina, an attractive hitchhiker on a lonely country road, who has escaped from the nearby lunatic asylum. Thugs waylay them and force his car to crash. When Hammer returns to semi-consciousness, he hears Christina being tortured until she dies. Hammer, both for vengeance and in hopes that "something big" is behind it all, decides to pursue the case.
In this drama, a trucker's business is nearly destroyed after he is wrongfully accused of killing a policeman with whom he recently quarreled.
When a woman goes missing on the eve of her wedding, her fiancee hires a detective to track her down
The relatives of a rich old woman unsuccessfully try to have her declared insane, so they can divide up her money. To show them that there are no hard feelings, she invites them to her estate for the weekend so she can decide to whom she actually will leave her money when she dies. Soon, however, family members begin turning up dead.
When it rains in the city, a serial killer known as "The Judge" looks for his next strangling victim. For months, the madman has been stalking at night, leaving behind clues, but police efforts have been fruitless. Constructing a life-size dummy of the murderer, police Lt. Harry Grant is growing obsessed with capturing him, and always following Grant is the relentless reporter Ann Gorman looking to break the story, but the hunt continues.
American Neil Bowman is traveling through France when he meets British photographer Lila. They are hired by French land owner Duc de Croyter to escort a Hungarian scientist to New York. But they soon realize that the job is not a cushy number, and have to deal with a gang of kidnappers who will stop at nothing to get their hands on the scientist
A young man who steals valuable Oriental objects for a crooked antique dealer is hunted down by the police after his latest Chinatown robbery turns violent.
Losing his memories of the last few days, neurologist Dr. Steele is told that his wife has been brutally murdered. Steele, aware of his conniving wife's infidelity, believes he may have been the killer and enlists the aid of his pretty nurse Stella to hypnotize him into recovering his lost memories.
Dutch painter Jan-Van Rooyer hurries to keep a rendezvous with Jacqueline Cousteau, an elegant, sophisticated Frenchwoman, slightly his elder, whose relationship with him had turned from art student into one of love trysts. He arrives and is confronted by Detective Police Inspector Morgan who accuses him of having murdered Jacqueline. Morgan listens sceptically to the dazed denials of Van Rooyer as he tells the story of his relationship with the murdered woman. Morgan, after hearing the story, realizes that the mystery has deepened, and it becomes more complicated when the Assistant Commissioner, Sir Brian Lewis, explains that Jacqueline was not married but was being kept by Sir Howard Fenton, a high-ranking diplomat whose names must be kept out of the case.
Monette, a recently separated travelling book salesman tells his grim story to both a priest and a hitchhiker, looking for absolution.
Jim Hanvey is a genial but top-notch detective who has retired to his country home. An insurance company hires him to find a missing emerald so they won't have to pay out the $100,000 for which the jewel is insured. It doesn't take him long to find the emerald, but he discovers that finding it was the easy part; the difficult part is getting it back to its rightful owner, and he winds up involved in a murder in which an innocent man is framed.
A private detective is hired to find a young heiress but finds himself accused of murder.
Newspaper reporter Michael Ward plunges into a nightmare of guilt, fearing that his "evidence" has sentenced the wrong man to death.
A drifter claims the money in an old bank account. Soon he finds himself the target of two men who turn out to be the sons of the man's old partner, who is now in prison because of a conflict with him over the money in that account.
A woman uses a deck of cards to predict death within 24 hours for a stranger sitting at a bar, then tries to help him remember who he is based on items in his pockets.
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.