The California-Yucatan Railroad, being built for the good of Mexico, is under siege by a gang of terrorists hoping to force its sale; no one can prove their connection to profiteer Marsden. Manuel Vega, aged co-owner, calls in the aid of his nephew James, great-grandson of the original Zorro. Alas, James seems more adept at golf than derring-do; but after he arrives, Zorro rides again! Can one black-clad man on horseback defeat a gang supplied with airplanes and machine guns?

Hammond, owner of the town's stagecoach line and a leading citizen, is opposed to Idaho becoming a state, and kills Randolph Meredith, owner of the town's newspaper, for endorsing it. Meredith's sister Barbara, expert with a bullwhip and pistol, dons a black costume and mask and becomes "The Black Whip", dealing a blow to Hammond and his gang each time they perform some heinous act in their efforts to keep the town, and their power over it, unchanged. Aided by government agent Vic Gordon, Barbara confronts Hammond in a final showdown just as the town votes on whether or not to accept statehood.

Tom Grant has found a rich gold vein and Bart Eaton is after it. Tom's sister Mary heads for the gold fields and Eaton and his men follow. Eaton teams up with Ace Daggett who plans to doublecross him and get the gold for himself. They frame Tom for murder and then try to get him to sign over his claim. The famous scout Tex Houston is on hand, escaping the attempts on his life, saving Mary from various perils, and trying to bring in the real killer and clear Tom.

Texas Ranger tries to stop takeover of Indian lands.

An expedition sets off for the last land of Mu, where legend has it that a killer death ray is emitted from the eye of a golden idol.

The masked hero leads a fighting force to fight a villian who plots the conquest of The Republic of Mexico.

This 13 chapter serial is based on the comic strip character Ace Drummond created by Eddie Rickenbacker. Ace is a 'G-Man of the sky' working out of Washington D.C. He is sent to Mongolia to find out why a mysterious villain known only as 'The Dragon' is trying to prevent the newly formed International Airways from setting up an airport there. Ace meets Peggy Trainor (Jean Rogers) who is searching for her archaeologist father who has disappeared. Together they search for answers to the puzzles.

Young Pauline is left a lot of money when her wealthy uncle dies. However, her uncle's secretary has been named as her guardian until she marries, at which time she will officially take possession of her inheritance. Meanwhile, her "guardian" and his confederates constantly come up with schemes to get rid of Pauline so that he can get his hands on the money himself.

When his father is killed in a train wreck, Larry Baker vows to unmask a mysterious criminal called "The Wrecker," who has targeted the L&M Railroad for deadly" accidents."