Sheriff John Higgins quits and goes into prospecting after he thinks he has killed his best friend in shooting it out with robbers. He encounters his dead buddy's sister and helps her run her ranch. Then she finds out about his past.
Summoned by Ed Oliver, Jim Hale and sidekick Fuzz arrive at Oliver's ranch to find a range war in progress. Unknown to Jim, Ed Brady has kidnapped Oliver and replaced him with a stooge. Brady is after the Green ranch and Jim and Fuzz now set out to help Helen Green.
Captain Matthews is paid 40,000 dollars in cash by Nick Conrad for his shipment of silk from China. About 15 seconds after he gets the cash, he's lured away on a false pretence and robbed by Conrad's henchmen. Newspaper reporter Jerry Mason witnesses the robbery and steals the cash from Conrad.
John Wyatt is a government agent sent to smash a counterfeiting operation near the Mexican border. Joining Doc Carter's medicine show they arrive in the town where Curly Joe, who once framed Carter, resides.
When John Mason's father is killed, John is wounded. Attracted to his nurse Alice, a conflict arises between him and his friend Ben who plans to marry Alice. John later finds the killer of his father but goes to face him not knowing Ben has removed the bullets from his gun.
A thug robs and kills a fur trapper. He is caught and locked up by the Mounties, but is soon broken out by his partner. As the Mounties investigate, they discover that the two are part of a ruthless crime ring run by a female gangster.
When Morley has his own bank robbed, Tom tries to break it up. Mistaken for one of the gang, he is caught and sentenced to a chain gang. His girlfriend Peggy then sets out to prove his innocence.
Hanson is using Bobby's carrier pigeons to receive messages. His man Slim shoots them down before they reach Bobby. When Slim is injured, Ranger Daniels posing as a drunk gets the job. He misses the next pigeon on purpose and gets the message from Bobby. But his identity has now become known and the gang rides to get him.
A fur trapper catches another trapper trying to steal his furs. He stops the thief, but later on the furs are stolen anyway. Rin Tin Tin Jr. tracks down the thief to try to get the furs back.
Rodeo star John Scott and his gambler friend Kansas Charlie are wrongly accused of armed robbery. They leave town as fast as they can to go looking for their own suspects in Poker City.
The son of Sheriff Clay Hartley, of the frontier town Elder, has gotten into bad company and hangs out with an outlaw gang in which, Collins, owner of the Golden Rule Saloon, is the secret head. Sheriff Hartley suspects him, but has been unable to gather the needed evidence. Collins instructs his gang, including young Hartley, to hold up the stagecoach on its return trip from Missionary Flats and take the cargo of gold dust it is carrying. Sheriff Hartley is notified of the planned holdup by one of his deputies who has been spying on Collins, and organizes a posse. A deputy-sheriff is killed in the ensuing gunfight between the lawmen and the outlaws, but Deputy Joe Larkin, pursues and captures Clay Hartley Jr. The latter is quickly tried and convicted of the killing of the deputy, and sentenced to be hung. Sheriff Hartley has only a few hours to prove his son was not the killer. He enlists the aid of Collins' step-daughter, Joan, who is in love with Hartley's son.
Grant hides stolen money in the luggage of Bonnie Shea who is moving west. Later when he and his men arrive to retrieve the money, they also kidnap Bonnie. This sends Reasonin' Bates and his cowhands on their horses after the gangsters in their cars.
Good-natured troublemaker "Cyclone" Tom Saunders is hired by a ranchers' association manager to investigate recent cattle rustling at one of their ranches and to see if a pair of nesters have anything to do with it. After discovering the nesters, pretty Betty Powell and her rickety old father, are incapable of rustling, Tom instead turns his attention to the huge, swaggering bully of a foreman, Nate Lenox.
When the ancient continent of Mu sank beneath the ocean, some of its inhabitant survived in caverns beneath the sea. Cowboy singer Gene Autry stumbles upon the civilization, now buried beneath his own Radio Ranch. The Muranians have developed technology and weaponry such as television and ray guns. Their rich supply of radium draws unscrupulous speculators from the surface. The peaceful civilization of the Muranians is corrupted by the greed from above, and it becomes Autry's task to prevent all-out war, ideally without disrupting his regular radio show.
Tom Riley and sidekick Windy arrive at the Baker ranch where horses are being rustled. It appears the culprit is a wild horse, but Tom catches and rides the horse which leads to trouble with the real rustlers.
Chris Morrell, the guardian of half-Indian girl Nina, is helping her find her missing white father. so she can cash in on her late mother's oil lease. Outlaw Sam Black is after the girl and her father as well. Besides dealing with the Black gang, Morrell has to find another robber, Jim Moore, who switches clothes with him after he finds Chris unconscious from a fight with Sam Black. Along the way, he meets a lady who's the sister of Jim Moore, another bad hombre who's in cahoots with Jim Moore, and an old friend who takes in Nina and helps Chris locate Nina's father and fight off the various desperadoes
Tobin is after the bandit Zanti who killed his parents. He finds him just as Zanti is about to kill Dusty and kidnap Ruby. Saving the two, he goes after Zanti. He catches him but Zanti escapes the Sheriff's handcuff's and this time Tobin has to chase him into the desert.