There is a card shark that didn't appreciate having his cheating be revealed, even if it was subtle. He is gunned down in the street. His brothers seek revenge, one brother is a little more cautious than the other. He wants to make sure they get the person who did the shooting or that the sheriff locates the person.

Orin and Ruth McKnight's May/December romance hits a rough spot when Bill Longley returns from a cattle drive with news that Orin's son from his first marriage died driving off rustlers. To make matters worse, Ruth's old beau has traveled all the way from Ohio to bring his former girlfriend home.

An alcoholic lawyer battles the local sheriff over voting procedures. Davis: Edgar Stehli. Sheriff: Robert Lowery. Longley: Rory Calhoun. Carlin: Charles Cooper.

Outlaws besiege a small town where their leader is jailed. Pete: Jon Locke. Cliff: R.G. Armstrong. Ruth: Mae Clarke. Atkins: Fay Roope. Mac: Wright King.

Longley, trapped by a landslide, is rescued by Johnny Hinshaw who the Texan soon discovers is on the run from the law. Johnny's accused of shooting a man after a quarrel and since he's already served a jail term and has two brothers on the run from the law he seems like a reasonable suspect to the sheriff - the more so since Johnny's sweet on the lawman's beautiful sister.

Longley has been made a special marshal to the Texas town of Rio Nada. The area has been plagued by Mexican bandits who have used it to cross the border into the United States and raid the countryside. The gang is led by a mysterious leader known only as "El Sombro". When Longley captures an agent for El Sombro, he hopes to use the threat of hanging for the attempted murder of a deputy sheriff to force him to identify the illusive bandit chief. (Note to viewers: Best to first view "The Terrified Town", then "Sixgun Street", then "The Taming Of Rio Nada", as this is the order in which the events are meant to take place even though the episodes originally aired in the reverse order).

After acting marshal Bill orders no guns to be worn on the streets of Rio Nada, a local casino owner sends for two notorious gunmen to kill him.

Bill finds a town engulfed by a feud between two ranchers. He also learns that his former commanding officer, now a doctor, has turned to drinking, and that a young man blames him for crippling his arm. Bill tries to talk the doctor into staying and not running from the challenges.