The Mysterious Mr. M

A famous scientist invents a humanoid robot (the titular "monster"), so a greedy rival scientist plans to steal it for use in his criminal plans. His henchmen often kidnap a trained gorilla (the titular "ape") from the zoo, to aid in the schemes.

Her Dangerous Path

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.

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.

A Martian invader crashes his spaceship conveniently close to the workshop of a scientist who is developing an interplanetary craft. If the extraterrestrial Purple Monster can complete the rocket ship and return to Mars, he will be able to start a full-scale invasion of Earth. Good thing Craig Foster sets out to thwart the Monster's mission!

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.

A 12-episode serial in which Tailspin Tommy evades volcanoes, anti-aircraft shells, and time bombs as he foils a plan by corrupt profiteers to steal an island's oil reserves.

Jerry Blake (aka Federal Operator 99) teams-up with Joyce Kingston to thwart the plans of escaped crime boss Jim Belmont.

An expedition arrives on an uncharted jungle island to rescue the local natives, led by a jungle boy, from a volcano that is about to erupt.

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.

When average, law-abiding citizens suddenly turn to a life of hedonistic behavior and violent crime, Detective Tom Beck is tasked with helping young FBI agent Lloyd Gallagher determine the cause.

An Indian rug is the key to the location of a lost treasure. When the rug's owner is murdered, it becomes a case for Forest Ranger Steve King

In this movie serial Professor Sturgess invents a miraculous engine which can draw unlimited power from the atoms of the air. When the professor is killed, his daughter and her fiance must fight to keep the secret of the power engine out of the hands of evil Weston Dore and his henchmen.

Reporter Brenda Starr and her photographer Chuck Allen get involved in a search for the loot from a payroll robbery. Cliffhanging action and adventure and a fair amount of comic relief follow them at every turn.

A bunch of waterfront youths pursue the Sea Raiders, a gang of saboteurs.

Government agents try to thwart smugglers, while some sort of plot unfolds, about a hidden treasure revealed by cursed coins.

Kit Cardigan seeks the killer of his father...among other plot threads leading up to the famous historical incident.

Government agents work to interfere with schemes to trick the Comanches into war with the Texans.