Sadistic killer-for-hire Philip Raven becomes enraged when his latest job is paid off in marked bills. Vowing to track down his double-crossing boss, nightclub executive Gates, Raven sits beside Gates' lovely new employee, Ellen, on a train out of town. Although Ellen is engaged to marry the police lieutenant who's hunting down Raven, she decides to try and set the misguided hit man straight as he hides from the cops and plots his revenge.
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.
The police arrest a man climbing over the wall of a cemetery after midnight. He claims that he is being blackmailed and is following instructions he received by mail to leave $1000 on a certain grave. It turns out that he's not the only one who got a blackmail letter from the same person--calling himself "The Black Panther"--and it also turns out that all the recipients are connected to an opera company.
A sheltered heiress falls for a charming playboy and elopes with him, but soon discovers his gambling vice and mounting debts. As his lies deepen and those around them meet mysterious ends, she begins to suspect that her husband’s affection may conceal a deadly motive—and that she could be his next victim.
Having forsaken the detective business for the safer confines of personal insurance, Gay Laurence is compelled to return to his sleuthing ways. Along with sidekick Jonathan "Goldie" Locke, he agrees to look into a series of home party robberies that have victimized socialite Maxine Wood. The duo gets more than they bargained for when a murder is committed at Wood's home, but Lawrence still finds time to romance the damsel.
Private detective 'Duke' Martindale and his wife, Phyllis, an attorney, are working together to clear a girl falsely convicted of murdering a judge. Two people who know the truth are killed and 'Duke' Is shot at. Despite some interference by Police-Sergeant Brent, and a dangerous automobile chase and 'Duke' and Phyllis finding themselves prisoners of the real murderers, the case is solved.
Allied spies and Nazi Agents insinuate themselves at a Scottish cottage (converted to a wartime hospital) with interests on an inventor's nearly perfected bomb sight.
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.
Newspaper magnate Charles Foster Kane is taken from his mother as a boy and made the ward of a rich industrialist. As a result, every well-meaning, tyrannical or self-destructive move he makes for the rest of his life appears in some way to be a reaction to that deeply wounding event.
A down-on-his luck businessman organizes an excursion to Sir Henry Morgan's Island for a treasure hunt only to encounter a mysterious phantom and murder.
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.
Sandy Vantine and her uncle, Paul Vantine, return from Europe with an antique cabinet purchased during their trip. Jim Moore, a reporter who had met Sandy and fallen for her during the voyage, suspects something odd about the cabinet. His suspicions are confirmed when people who have touched the cabinet mysteriously die. Jim and Sandy set out to solve the mystery before anyone else can become a victim.
Millionaire sportsman Hiram Brighton hires gumshoe Michael Shayne to keep his spoiled daughter Phyllis away from racetrack betting windows and roulette wheels. After Phyllis slips away and continues her compulsive gambling, Shayne fakes the murder of her gambler boyfriend, who is also romancing the daughter of casino owner Benny Gordon, in order to frighten her. When the tout really ends up murdered, Shayne and Phyllis' Aunt Olivia, an avid reader of murder mysteries, both try to find the identity of the killer.
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.