The period is the 1820's and the first wagon train leaves Independence heading west to Santa Fe. In order to maintain his power, the ruthless Official at Santa Fe must not let them arrive and he sends out his men to stop them. The wagon train then has to endure repeated attacks but is aided by a mysterious rider that shoots singing arrows and rides a painted stallion.

Crash Corrigan, a recent graduate of Annapolis, and Diana, a go-getting reporter, join Professor Norton for a search for the source of a string of earthquakes, Atlantis. They ride Prof. Norton's rocket submarine searching the sea and little Billy Norton, the professor's son stows away, of course. When they find Atlantis they are caught in a war between peaceful Atlanteans, note their white capes, and war-monging Atlanteans, note their black capes. After many harrowing moments for Crash, Diana, Prof. Norton and Billy, they barely get away with their lives when they escape a tower of Atlantis raised to the surface for the sole purpose of dominating or destroying the Earth (Which one depends on the compliance of the upper world dwellers.)

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?

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.

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.

Flash Gordon, Dale Arden and Dr. Zarkov return to the planet Mongo for an antidote to the Purple Death, which wreaking destruction on Earth. However, Ming the Merciless has other plans for them.

Hank Davis, foreman on a huge dam project, enlists the aid of his two flyer friends when a sinister figure known as The Black Ace leads his Mystery Squadron of masked pilots in an attempt to destroy the dam.

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."

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.

Enemy spies try to steal a new fighter plane.