The Wild West adventures of Ben Cartwright and his sons as they run and defend their Nevada ranch while helping the surrounding community.

In 1865, Captain Mark Smith of the Confederate Army leads a band of deserters to conquer Texas and rule it as a dictator. In one of his first actions, he captures and assumes the identity of Texas' new Finance Commissioner, Colonel Marcus Jeffries, after having the real man murdered. When a contingent of Texas Rangers enters the territory, Snead, one of Smith's men, leads them into an ambush by Smith's "troopers". The Rangers are apparently wiped out, although one injured survivor is left. The survivor, nursed back to health by Tonto, swears to avenge the massacre and defeat "Colonel Jeffries" and his men.

Nat Cutler, known as Hawkeye, is a fur trader. With his faithful Indian companion Chingachgook, the last of the Mohican tribe, he fights to protect settlers against the raiding Huron Indians.

Cowboys and a businessman compete to find lost treasure.  

Buck Sherman and Jake Jackson, a couple of evil carpetbaggers, illegally enter a Navajo reservation to prospect for gold and end up killing Aranho, the Navajos chief. Black Arrow, presumed Aranho's son, refuses to kill the Indian agent, Tom Whitney, in revenge, as demanded by Navajo law. Then, he is driven off the reservation for his reluctance to kill Whitney and decides to join forces with Pancho, Mary Brent and the agent to go in search of the men who killed the chief.

A prospector is murdered by The Cactus Kid and his gang, who hope to find the murdered man's goldmine. The miner's dog, Rin-Tin-Tin, recognizes the killers, who thereafter seek to use the dog to locate the lost mine. With the help of a government agent and a young girl, Rinty saves the mine and brings the bad guys to justice.

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.