A Scotland Yard inspector and his reporter friend arrive on vacation in a small village and are immediately involved in what is claimed to be a murder but the body has disappeared, leaving it to the inspector to find the body, determine the motive and find the killer.
Having once again avoided criminal conviction, Professor Moriarity develops a murderous plan to “finish off” his last major nemesis, Sherlock Holmes, by making him fail to prevent the perfect crime. Does it involve a family curse, the crown jewels of England, or something else…
Detective Guy Johnson's client, Willie Heywood, is framed for murder. While Guy hides him so he can catch the real killer, both of them are nabbed by the police, tried, convicted and sentenced to jail: Guy for a year with Willie to be executed. On the way to jail, Guy comes across a clue and escapes from the police.
Suave private detective Simon "The Saint" Templar arrives in San Francisco and meets Val, a woman whose police inspector father killed himself after being accused of corruption and dismissed from the force. Convinced of the man's innocence, Templar takes it upon himself to vindicate the memory of Val's father. To do so he must take on the city's most dangerous criminal gang, while also battling hostile members of the police department.
An investigator for the District Attorney's office quits to open his own detective agency. However, business is so bad that he finally decides to give it up and go back to his old job. As his wife is at his office closing up, a wealthy society matron walks in with a case: she wants to know if her husband is having an affair with his ex-girlfriend, who is now married. The wife accepts what looks to be an easy case, figuring than she can then persuade her husband to re-start the agency. However, when the client's husband is found murdered, she decides to investigate the murder herself. Her husband has also been assigned by the D.A. to investigate the murder, and he doesn't know that his wife is also on the case. Complications ensue.
Nick and Nora Charles investigate when Nora's cousin reports her disreputable husband is missing, and find themselves in a mystery involving the shady owners of a popular nightclub, a singer and her dark brother, the cousin's forsaken true love, and Nora's bombastic and controlling aunt.
Sir Borotyn, a prominent Prague resident, is discovered murdered in his home, with all indications pointing to a vampire assault. The victim's friend, Baron Otto, and the physician who analyzes the body, are certain that the vampire is the mysterious Count Mora or his daughter. Receiving little help from the law, Professor Zelen, an expert in the occult, is called in to assist with their investigation.
Investor Robert Norman murdered before meeting. Police investigate. Journalist Claire Haines pursues story to impress editor. Intertwining narratives of crime solving and reporting unfold.
In a spooky hotel on the coast of France, two bands of crooks are working independently of the other in an attempt to steal the inherited fortune of an American girl, Sue Tally. Along the way the heiress is kidnapped, three murders are committed, a girl appears in two places at once, mysterious persons roam about the old hotel at night and mysteriously disappear, and there is a hidden room without any doors.
As the demand for raw silk goes sky high, crooked businessman Wallace Myton corners the market with plans to drive up the price. Determined to fulfill his contracts, manufacturer Donald Kilgore imports $3 million worth of silk to Seattle and accompanies it by special train to New York. But when his secretary is found murdered, Kilgore soon discovers Myton has planted three killers on board with orders to stop the express and its passengers dead in their tracks.
Con-man Chandler and his partner Frank decide to start a clairvoyant act. Chandler falls for Sylvia, one of their marks, but their relationship is challenged when his deception impacts others' lives and Sylvia urges him to reform.
John Mason returns to the Sally Ann mine to claim his half share. Janet Cater also returns although her father lost his half share to Joe Ryan. Ryan and his gang are also there to get the gold. A mysterious Phantom is also present. Mason's plan to expose Ryan as an outlaw and to force him to turn his share to Janet works. But when distracted by the Phantom, John is made a prisoner by the gang.