A police detective is caught up in a plot to steal two million dollars in bonds.
A team of two-fisted insurance investigators (one of whom disguises himself as The Masked Marvel) endeavor to discover and thwart the loathsome saboteur Sakima.
Congo Bill is hired to locate an heiress lost somewhere in Africa.
Claire Forrest seeks her kidnapped scientist father, hidden somewhere on Mystery Island. He is held and forced to work on diabolical inventions by Captain Mephisto, a costumed villain.
Dr. Ernst Grood , having already dominated the planet Ergro, now intends to take over the control of the Earth. Unfortunately for him, reporters oppose his sinister designs.
Greedy traders have kidnapped a researcher, hoping he will reveal the location of a treasure in a hidden village. Family and friends of the researcher come looking for him. Adventure ensues.
Kit Cardigan seeks the killer of his father...among other plot threads leading up to the famous historical incident.
Beatrice Fairfax, the original advice-to-the-lovelorn reporter and her friend and not-so-secret admirer Jimmy Barton investigate calls for help and escape exotic perils and dangers. Episodes include exciting and fun stories of baby-napping, blackmail, jewel thievery, disguise, counterfeiting, and the long-unseen episode featuring entrancing cult starlet Olive Thomas and the real New York Yankees and Giants playing a game in the Polo Grounds.
Jerry Blake (aka Federal Operator 99) teams-up with Joyce Kingston to thwart the plans of escaped crime boss Jim Belmont.
Escaped Prisoner 39013 impersonates the rich and influential Horace Granville, allowing him to create a variety of disasters. Fortunately, he is thwarted repeatedly by three daring circus daredevils.
Prior to the United States' involvement in World War II, the masked vigilante Spy Smasher fights Nazi agents operating within the US, led by the treacherous sabotage leader codenamed The Mask.
A young girl journeys to Africa to find her father, an explorer who vanished in the jungle.
Two British officers are assigned to collect information to convict Captain Kidd of piracy.
Mota is a Martian representative, who has come to impose interplanetary law on the Earth (which has become too dangerous); opposing his authority is Kent Fowler, who resists the alien plot, without understanding its details.
A bunch of waterfront youths pursue the Sea Raiders, a gang of saboteurs.
Mystery and adventure, surrounding a stolen rubber harvest.
Four flying G-Men protect America against enemy spies; one of the four assumes the identity of The Black Falcon, to befuddle the saboteurs even further.
Pulp hero "The Spider" seeks to destroy all criminals. In this serialized adventure, he battles The Octopus, who intends to replace the government of the United States.
Mandrake and his team attempt to prevent "The Wasp" from stealing and using a new Radium invention.
Disaster seems imminent when scientists discover that the planet Mongo is about to crash into Earth. Luckily, heroic young Flash Gordon is on hand to lead an investigative mission into outer space and onto the speedily approaching planet. There, he and his best girl, Dale, who is along for the ride, learn that Ming, the devious ruler of Mongo, has purposely put the planet on a collision course with Earth, and only Flash can stop him.