Shipping magnate Cyrus Wentworth, downcast over a disaster to his ocean liner 'Wentworth Castle' (carrying, oddly enough, an illicit shipment of Chinese bonds) is shot in his office at the very moment of kicking out his daughter's fiance Dick Fleming. Of course, Captain Street arrests Dick, but reporter Bobbie Logan, the attractive thorn in Street's side, is so convinced he's wrong that she enlists the help of detective James Lee Wong to find the real killer.
After intrepid working girl Mary Carter becomes the new owner of a reputedly haunted mansion located off the Cuban coast, a stranger phones warning her to stay away from the castle. Undaunted, Mary sets sail for Cuba with a stowaway in her trunk—wise-cracking Larry Lawrence, a radio announcer who helps Mary get to the bottom of the voodoo magic, zombies and ghosts that supposedly curse the spooky estate.
Although young and beautiful, schoolteacher Anne Gladden fears a dull future. She finally decides to take a walk on the wild side, splurging on some fashionable new clothes and setting off to find adventure. Her new confidence inspires her to flirt with complete strangers. When a gangster pays unwanted attention to her, she ditches him and flees in his car, unaware that there's a corpse in the trunk. Determined to recover his stolen vehicle and its incriminating cargo the thug begins a desperate search. The oblivious Anne, comes to the aid of a handsome young man stranded alongside the road. Romance blooms, but after the shocking discovery of a body in the trunk, the duo decide they have to return the car. The bickering lovebirds head back to the city, trailed by both the angry gangster and the cops, who suspect the young couple of murder.
When a police officer is murdered, Captain Street looks to Mr. Wong to catch the killer. Prime Suspect: Frank Belden Jr., whose father is a businessman well known for both his success and dishonesty. Mr. Wong faces increasing danger and is nearly executed himself as the investigation develops in treachery and complexity. As Mr. Wong follows the trail of dead bodies, he uncovers a jewel smuggling ring on the San Francisco waterfront and a case much larger than the death of a police officer.
When the plane owned by the "Yukon and Columbia Mail Service" crashes, RCMP Sergeant Renfrew (James Newill) and Constable Kelly (Dave O'Brien) suspect murder. Their suspicions are confirmed when Renfrew finds the control stick has been jammed, forcing the plane to fly in one direction until the gas ran out. Mine owner Louise Howard (Louise Stanley) reports that her superintendent is missing. The Mounties find him murdered and that too has been made to look like an accident. A new mail service pilot, Bill Shipley (Warren Hull), arrives. He had gone to training school with Renfrew but had been cashiered for misconduct. The Mounties discover that Raymond (Karl Hackett), who had been working for Louise, really owns the flying line managed by Yuke Cardoe (William Pawley.) They find proof that all the gold from the mine isn't being turned over to Louise, and suspect that Raymond and Yuke are stealing the gold and shipping it to Seattle by plane.
When news reporter Walter Garrett arrives at the hotel room of bombshell actress Angela Merrova to conduct an interview, he finds her dead from multiple stab wounds. He returns with the police to find the hotel empty and the body vanished. Garrett writes about the incident but is fired when Merrova, alive and well, goes to the paper to complain. Now his only chance to get his job back is to find the truth, which involves the grisly scheme of a madman.
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…
A pretty Chinese woman, seeking help from San Francisco detective James Lee Wong, is killed by a poisoned dart in his front hall, having time only to scrawl "Captain J" on a sheet of paper. She proves to be Princess Lin Hwa, on a secret military mission for Chinese forces fighting the Japanese invasion. Mr. Wong finds two captains with the intial J in the case, neither being quite what he seems; there's fog on the waterfront and someone still has that poison-dart gun...
When an escaped circus gorilla appears to have gone on a murderous rampage, a threatened attorney calls on the detective trio of Garrity, Harrigan and Mullivan to act as bodyguards. In short order, we discover that there is more to the attorney than meets the eye, and the ape may be innocent after all. When a pretty young heiress faces peril, it's up to our heroic trio to save the day.
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.
Detective James Lee Wong must find the "Eye of the Daughter of the Moon," a priceless but cursed sapphire stolen in China and smuggled to America. His search takes him into the heart of Chinatown and to the dreaded "House of Hate" to find the deadly gem before it can kill again.
In England, an eccentric police inspector, an earnest test pilot and a spunky female reporter team up to solve the mystery of a series of test aircraft which have disappeared without a trace while over the ocean on their maiden flights; unaware, as they are, that a spy ring has been shooting the planes down with a ray machine hidden aboard a salvage vessel which is on hand to haul the downed aircraft aboard, crews and all.
While participating in a contest at a local newspaper in which school children are asked to submit a news story, local attorney Carson Drew's daughter Nancy intercepts a real story assignment. She "covers" the inquest of the death of a woman who was poisoned. Nancy doesn't think the young woman accused of the crime is guilty and corrals her neighbor Ted into searching for a vital piece of evidence and stumbles onto the identity of the real killer.
A Japanese man claiming to be Mr. Moto, of the International Police, is abducted and murdered soon after disembarking from a ship at Port Said in Egypt. The real Mr. Moto is already in Port Said, investigating a conspiracy against the British and French governments.