Idaho!

Disaster seems imminent when scientists discover that the planet Mongo is about to crash into Earth. Luckily, heroic young Flash Gordon is on hand to lead an investigative mission into outer space and onto the speedily approaching planet. There, he and his best girl, Dale, who is along for the ride, learn that Ming, the devious ruler of Mongo, has purposely put the planet on a collision course with Earth, and only Flash can stop him.

King of the Candian riding police is up against Japs and Nazis who are about to invade Canada. They just want to clear the way with a new futuristic plane called "The Falcon" first, but that's not gonna happen if Kig has his way.

Lieutenant Commander John Byrne of the Naval Secret Service and his partner Pvt. Bill Riggers chase criminal Dr. Sin Fang, who is desperate to find a lost sacred seal. (The fifth and only surviving episode of a six-part serial about an evil mastermind inspired on Sax Rohmer's Dr. Fu Manchu.)

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

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.

Adventures of an American Secret Service-girl in search of an important German secret during the war. Chapters: [1] “The Great Secret,”; [2] “Marked for Death,”; [3] “The Gas Chamber,”; [4] “Below the Waterline,”; [5] “The Acid Bath,”; [6] “The Unknown,”; [7] “The Betrayal,”; [8] “A Crippled Hand,”; [9] “Woes of Deceit,”; [10] “The Inn of Dread,”; [11] “The Death Studio,”; [12] “The Chance Trail,"; [13] “Wings of Mystery,”; [14] “The Hidden Way,”; [15] “The Secret Host"

A serial in 12 chapters. Tarzan goes to Guatemala to find his lost friend, D'Arnot. On the way he helps Major Matling search Mayan ruins for hidden jewels and an idol containing the formula for a powerful explosive. D'Arnot and the idol are rescued, but the idol falls into the clutches of the explorer Raglan.

A beautiful young woman is a daring master thief. She meets the young millionaire Thomas Babbington Norton, while fleeing from the scene of her latest theft.

A 15-episode serial involving the land rush, gold mines, stolen maps, etc.

15-episode serial directed by Paul Hurst and J.P. McGowan.

A mad scientist named Dr. Satan plots to steal key pieces of technology to enable him to build an army of robots based on his prototype to conquer America. The only one standing in his way is Bob Wayne, who fights Satan as the enigmatic Copperhead. Mysterious Doctor Satan is a 1940 film serial named after its chief villain. Doctor Satan's main opponent is the masked mystery man, "The Copperhead", whose secret identity is Bob Wayne, a man searching for justice and revenge on Satan for the death of his step-father. The serial charts the conflict between the two as Bob Wayne pursues Doctor Satan, while the latter completes his plans for world domination.

The Wrecker wrecks trains on the L & R Railroad. One of his victims is Larry Baker's father. Baker wants to find the evildoer, among a host of suspects, but it will be difficult since the Wrecker can disguise himself to look like almost anyone