The second and final Grand National Pictures film to feature The Shadow, played again by Rod La Rocque. In this version, Lamont Cranston is an amateur detective and host of a radio show with his assistant Phoebe (not Margo) Lane. Cabbie Moe Shrevnitz and Commissioner Weston also appear.
Jeffrey Clavering is hired in London by The Great Eastern Oil Corporation to go to Paris to prevent unscrupulous industrialist Nikolai Kamarov from gaining control of their oil fields and turning them over to a foreign power.
U. S. Customs Agent Tom Evans is given the assignment of running down a smuggling ring which hijacks Canadian fur-shipper's trucks and sells the loot in the United States.
Pepe Le Moko is a notorious thief, who escaped from France. Since his escape, Moko has become a resident and leader of the immense Casbah of Algiers. French officials arrive insisting on Pepe's capture are met with unfazed local detectives, led by Inspector Slimane, who are biding their time. Meanwhile, Pepe meets the beautiful Gaby, which arouses the jealousy of Ines.
A young, newly-appointed rookie state trooper, John Shields, is celebrating with his sister Jane, his younger brother Freddie and Tom Marlin, Jane's fiancé and also a trooper, when they hear over the radio that two bandits have just killed a lawyer and his watchman. John and Tom set out in their patrol cars in hopes of capturing the killers, followed by Freddie who hopes some day to qualify as a trooper. Freddie encounters the two two bandits, Spike Doland and Butch and manages to get away with the bag of gold they had stolen. While chasing Freddie they are recognized by John who they kill when he tries to arrest them. Freddie then takes matters into his own hands in seeking to capture the killers of his brother.
Mickey Lofton, young half-brother of famed war-aviator Jerry, fails in his attempt to enter the Canadian Air Corps, because of his fear of thunderstorms developed by an incident in his boyhood days. Jerry, now a Captain in the U.S. Department of Justice, is given an assignment to capture some border oil smugglers. Through his friendship with Raoul McGuire, one of the suspects, Jerry is accepted as a member of the gang. Mickey is in love with Raoul's sister, Molly. Gang leader Moran shoots and wounds Raoul, and is himself shot down by Jerry. Mickey flies Molly and her wounded brother to a hospital. Jerry takes off in another plane to guard Mickey's craft from a pursuing airplane, and crashes his plane into the gangster's plane but parachutes to safety.
Holmes takes a vacation and visits his old friend Sir Henry Baskerville. His vacation ends when he suddenly finds himself in the middle of a double-murder mystery. Now he's got to find Professor Moriarty and the horse Silver Blaze before the great cup final horse race.
Cowboy Larry O'Day and his sidekick Lucky Smith happen upon a distraught Barbara Hartwell, who is about to be arrested for the murder of her uncle. With Barbara behind bars, Larry is determined to find the real killer and soon finds himself in the middle of a mystery involving crazed German entomologists and a smuggling ring bringing Chinese "picture girls" across the Mexican border for sale to wealthy Chinese bachelors.
As the sheriff of a small western town, Autry sings his way into a relationship with Eleanor, a singer from a Chicago nightclub who earlier witnessed a murder.
Frankie Reynolds (Frankie Darro' ), youngest member of a family of jockeys, borrows $4.85 (yes, four dollars and eighty-five cents) from his sister Phyllis (Gladys Blake), who is not a jockey, to buy a crippled colt from the stables owned by Clay Harrison (Kane Richmond). He nurses the colt back to health, and in two years has one of the fastest horses in the country.
A Professor has an invention that will bring down planes causing them to crash and Dawson is forcing him to use it on those carrying money. When Tim arrives to investigate he is mistaken for a noted outlaw. So he assumes that identity to force Dawson to make him a partner. But just as a plane bringing Tim help is arriving, his true identity is revealed and while he is a prisoner, Dawson forces the Professor to start his machine.
Dan Adams resigns his position as prosecutor on the district attorney's staff and sets out to clean up a gang of fake-accident racketeers. He gets a job with an insurance company, and assures the company president he will get the goods on the gang or die in the attempt. At the company offices, he meets Carol Carter and she, believing he is a shyster (possibly redundant) lawyer in the employ of the racketeers gives him as little help as possible. Dan visits his brother Eddie, who is mixed up with the gang and tries to make him break away. Eddie is belligerent but finally, because of the pressure brought by Dan and his wife Tonia, agrees to go straight. The gang, led by "Duke" Trotti, fears he will squeal and they kill him, plus they make his death look like an accident and plan to collect on it. Dan is closing in on the gang when Carol, who is now his assistant, comes up with some conclusive evidence, but "Duke" has plans to get rid of her before she can give the information to Dan.