US Border Patrolman Roy Rogers is assigned to prevent a herd of diseased cattle from crossing over from Mexico.

The big national crime syndicate has moved into town, partnering up with local crime boss Nick Scanlon. McQuigg, the only honest police captain on the force, and his loyal patrolman, Johnson, take on the violent Nick.

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.

The Devil arranges for a deceased gangster to return to Earth as a well-respected judge to make up for his previous life.

A singing entomologist (Roy Rogers) acts meek to help a juggling sheriff (George "Gabby" Hayes) solve ranch raids.

Dick Tracy goes up against a villain known as The Ghost, who can turn himself invisible.

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 Canadians have discovered a valuable substance called Compound X, which can cure infantile paralysis. When a country at war with Canada learns that Compound X also contains magnetic properties that could aid them in their warfare against the British, they send agents to infiltrate Canada and steal a large quantity of the substance. It's up to Sgt. King (Allan Lane) and his Mounties to track down the agents and put an end to their scheme.

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.

Homesteaders are moving into the valley settled many years ago by rancher Craig Dolan. He wants to keep them out by legal means but his nephew Bart brings in outlaws to drive them out. The Lone Ranger is on hand to help the homesteaders battle Bart's men as he overcomes traps, ambushes, burning buildings and other obstacles in his attempt to bring peace to the valley.

Young Englishman inherits ranch which he wants to sell, but Gene's gonna turn him into a real westerner instead. When new owner Spud arrives from England, Autry convinces him not to sell the ranch but to raise horses for the Army. When both Autry's and Neale's bids are the same, the Colonel calls for a race to decide the winner. But that night Neale has Autry's stable burned.

American federal agent Clark Stuart is on assignment in Santa Fe to draw up a trade agreement with the newly installed Mexican governor. Meanwhile, Walter Jamison leads a wagon train from Missouri, hoping to take advantage of the new agreement. Among Jamison's passenger are famed frontiersman Jim Bowie and a very youthful Kit Carson. The destinies of all these personalities intersect when villainous ex-governor DuPrey schemes to undermine the treaty and take over the New Mexico territory for his own vile purposes. Somewhere along the way, Davy Crockett joins the "good guys" in their efforts to thwart the despicable DuPrey.

A crooked real estate manipulator sells worthless land on mortgage to flood refugees, then tries to profit by reselling the land to the state, committing murder in the process, as the Three Mesquiteers work to bring him and his gang to justice.