A beautiful woman tries to avoid her marshal husband for his own protection, because a gang of robbers is planning on killing him over a robbery he foiled, thanks to her warning. She draws Slim in to help but Jess thinks she is bad luck.
Jess is appointed temporary sheriff of Laramie. Luke Wiley is a notorious, coward, bounty hunter dubbed "The Jackal" because he brings in his prisoners dead, and now he wants to take in a friend of Jess who is wanted for murder.
Slim along with the stage driver protect $10,000 of stage line money he is taking to Jack Adams. However, when the driver steals the money killing Adams in the process, Slim uses a friendship with driver's girlfriend to find the money.
Andy runs away after Slim wants to sell his horse which was returned after being stolen a year earlier but is causing damage. He runs into the outlaws who had his horse. The leader wants to keep him but the two partners want him dead.
Jess rides to Danver's Pass to help Dan Preston who wrote him and to whom he owes a favor. However, when he arrives at Danver's Pass no one knows of Dan but it is obvious to Jess that everyone is lying under orders from Matt Jessup.
While rounding up mustangs, Slim and Jess rescue Luke Gregg who is being chased by Sioux on their hunting grounds. Luke hires on to help break the mustangs but Jess becomes suspicious of him when knows too much of Slim's background.
The stage line is paying a bonus for all the horses they can provide by July 1. Jess decides to visit Sam Bronson in Colorado with the hope of buying several horses cheap. However, outlaws along with Sam's daughter cause problems.
As the Laramie marshal is killed by the Torrey gang, his new deputy arrives on the stage for Laramie. He and Jess get off on the wrong foot so when he needs a posse, Jesse refuses until a neighbor is killed then new issues arise.
Sam Jarrad, once a bounty hunter but now a sheriff in Colorado, is after the killer of Blake Wilkie. When his prime suspect says Jess did it, Jarrod goes after Jess but he seldom returns with a live prisoner. Slim hopes to change that.
Slim goes to Laramie for supplies only to find the town deserted except for a few women due to a rumor about a gold strike. An outlaw gang created the rumor to make it easy to rob the bank. The trapped Slim must fight them alone.
Slim finds old hatreds surface when Fran Ericson returns to Laramie at the same time a group of men have messages for Slim and the other relay stations. She wants vindication for her father being run out of the stage line Slim backs.
When the son of a neighbor is accidentally shot on Sherman property, it reopens an old wound for his father Ben in the feud between the Sherman's and Pakison's. Ben publicly challenges Slim to an old time duel that Slim wants to avoid.
Christmas Eve at the ranch with the Sioux on the warpath and a Mexican bandit after the gold on the stage. It arrives with the Sioux attacking, and five passengers including an orphaned boy, a widow, a gun-runner and a feuding couple.
Slim and Jess collect a $2000 bounty on a man they killed after stealing their horse. After collecting the bounty, they learn the dead man is really a sheriff chasing the man they thought they killed who returns to steal the money.
Clay Jackson, the Robin Hood of the west, saves Jess from three Sioux braves and then holds up the stage. He robs the banker but gives money to an elderly couple. Only the banker will testify against him, pitting Slim against the town.
Slim's new hand Joe Cloud, an Indian, is killed by neighbor Carl Vail when he finds Joe skinning his cow with a broken leg. He kills Joe using an Indian method. Slim presses charges against Vail but finds himself ostracized by Laramie.
Jess is forced by a released convict Clint Wade to take him to Utah where Jess killed Clint's brother who hid $80,000 there. Clint thinks Slim is following them to rescue Jess but the it turns out an old cell mate wants the money, too.
Slim and Jess are to meet George Lake in Jackson City to buy cattle but Lake has sold his herd, infuriating Slim. When Lake is shot on the street and Slim is found by the body, he is arrested. It is up to Jess to solve a strange case.
When a sick passenger arrives on the stage, Slim and Jess try to help him but are surprised when he is a she. On top of that she is looking for Jess who wants nothing to do with her as her family are all outlaws but Slim thinks otherwise.
A wounded outlaw sends his brother for a doctor who mistakes the vet Slim has gone for, for a doctor when Slim calls him doc. He kidnaps the pair along with a female dealer being run out of town taking them to the gang's hideout.
An injured marshal is taking a prisoner to Cheyenne to testify at a trial. The wife of the man on trial wants the prisoner as does the man's gang but for different purposes. They all end up at the Sherman ranch when the marshal needs help.
After one man is killed and Slim is wounded, Jess goes after the shooter who was riding a pinto. He loses the trail but rides to Rimrock where he finds the pinto. He confronts the owner who happens to be the sheriff of Rimrock.
Slim's neighbor Cory who is half Cheyenne is thinking about inviting some of his tribe to move to the ranch he inherited from his white father. However, his uncle and cousins have other ideas. Slim wants to help him but Cory is wary.
Slim is asked by an eastern professor to guide him to a gold strike a friend found a decade earlier. Two of Slim's mischievous neighbors follow them hoping to make a killing but everyone has been mislead as the professor is a killer.
Jess as acting deputy frees a bounty hunter's prisoner who had cut down Jess during a lynching five years earlier saving his life. Having paid his debt, he decides to see if the prisoner was truly innocent himself or should be recaptured.
Jess finds a starved drifter who thinks Jess wants to shoot him. Slim and Jess offer him a job as he turns out to be a good worker but very reclusive. The father of a man he killed in a fair fight is sending hired guns after him.
A test of friendship is brought to the forefront when Jess learns that an old friend has stolen an Army payroll. He is asked by Major Stanton to find and return veteran Sgt. Billy Jacobs who has gone AWOL but once saved Jess' life.
A prisoner is killed by the son of a broke farmer as they transport him to the tumbleweed wagon for pickup. Needing the $100 for the job the farmer decides to substitute Slim when they find him alone on the road putting Slim in danger.
Jess is riding shotgun with a $30,000 Army payroll on a stage with three passengers using a special route. It is still held up as he learns the driver tipped off the robbers who decide to leave them all stranded in the desert.
When Slim holds off outlaws from a gang run by Doc Longley who saved him when he was six, Doc calls on Slim to help clear his name. A deputy shot in the back was planted on his ranch. Slim reluctantly tries to help but there is no proof.
Jess is asked for help by old partner Dixie Howard, who once saved Jess' life, after being wounded and killing a friend of Jess. Dixie is with his beautiful girlfriend but she and Jess soon realize the old Dixie is no more.
With the Sioux attacking the stage, Slim suggests they repair an old road the Sioux will not attack. He has stage driver Lon MacRae gather a work crew which seems to be an odd group of men. When they die one by one, no one knows why.
Slim is sent to renew a lease right of way for the stage line but finds the woman owning the ranch in financial trouble. Her husband was killed and suspected of robbing a $30,000 payroll. Slim decides to help but may be in too deep.