Nancy Evans, lovely circus owner, has a ranch that she's never visited, but for sentimental reasons won't sell to Mike Abbott. Her partners, secretly in league with Abbott, sabotage the circus to force Nancy to sell the ranch; instead, she goes there to live. Will her neighbors, the Three Mesquiteers, be a match for the secret swindlers? And what's so valuable about that run-down ranch anyway?

Two men with questionable pasts, Glyn McLyntock and his friend Cole, lead a wagon-train load of homesteaders from Missouri to the Oregon territory...

When the unscrupulous Carlos Manning discovers that an old Spanish land grant recently unearthed will leave a huge section of California real estate to the heirs of Don Quantero, he employs Mel Donovan and his killer henchmen to murder them all. That will leave Manning as the sole heir to millions. However, Delores Quantero tumbles to this plot and enlists the aide of two-fisted reporter, Cliff Roberts to save all her relatives

Indian scout Tom Jeffords is sent out to stem the war between the American settlers and Apaches in the late 1870s Arizona. He learns that the Indians kill only to protect themselves, or out of retaliation for white atrocities.

A dedicated FBI agent recalls the agency's battles against the Klan, organized crime and Communist spies.

A 12 episode serial starring Rex, the King of the Wild Horses and Rin-Tin-Tin, Jr. Rex is brought from the island of Sujan, where he is worshiped as a God-Horse, to the U.S. to be trained as a polo pony. He escapes, meets Rinty and with the help of Frank Bradley is returned to Sujan. The natives have been persuaded to turn against their God-Horse, however he is rescued just in time before he is burned as a sacrifice.

A group of "Phantom Raiders" interfere with a cattle drive from Texas to Abilene; fortunately, U.S. Marshal Wild Bill Hickok is appointed to ensure the success of the mission.

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.

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.