Although ostensibly the grand-son of the legendary hero, Clayton Moore's Ken Mason is little more than a cowboy in a black mask in this 12 chapter Republic serial. Mason, the head of the telegraph line work crew, assumes his ancestor's trade-mark mask (but not whip) in order to prevent a local czar (Roy Barcroft) from sabotaging the burgeoning telegraph line. Pamela Blake, a brunette starlet forme...

In Africa, a deceased medical missionary's daughter in Africa carries on her father's work. Before long, she finds herself in danger from crooks and a local witch doctor.

Jesse James wants to start a new life in a new location, but quickly finds himself wrapped-up in protecting townsfolk from the machinations of evil oilmen.

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.

Stock-footage from Republic Pictures' earlier Zorro serials was served up once again in this 12 chapter cliffhanger, this time without the financially strapped studio having to credit Zorro creator Johnston McCulley or pay any royalties. Zorro simply became "Don Daredevil" (Ken Curtis), a foppish Easterner by day turned masked avenger by night. Like his not too distant relative, Don wore his disgu...

Two federal agents battle a gang that hijacks trucks carrying materials vital for the security of the country and sells them to foreign powers.

Prof. Millard pretends to be dead and helps Jeff King ferret out Vulcan, the evil traitor at the science academy. Donning his Rocket Man costume King goes from one hair raising rescue to the next in order to keep the newly invented Decimator out of the clutches of Vulcan and his minions.

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.

Martians come to Earth to build an H-bomb strong enough to blast Earth out of orbit so that Mars can be moved into its place in closer proximity to the sun. Super-scientist Larry Martin, inventor of the first stratospheric-flight spaceship as well as a jet-powered personal flying suit with helmet, is called upon by the government to investigate ramped-up UFO reports occasioned by the Martians' sp...

A criminal mastermind known as The Crimson Ghost is out to steal a device called the Cyclotrode, which can short-circuit all electrical current on the planet.

Commando Cody, 'Sky Marshal of the Universe', works with American scientists Joan Gilbert and Ted Richards in the development of a flying suit and a rocket to the Moon. When the nation's defences are being sabotaged and destroyed, Cody learns that an atomic-gun is being used and that the men on the moon are the culprits.

Man-woman team of investigators uncover a gang whose mad scientist leader has developed an invisibility chemical and plans to build a mercenary army of invisible men.