Jamie deliberately disobeys Ben's order not to drive the supply wagons. During his recklessness, the wagon goes out of control on a sharp curve and is wrecked. Nobody is hurt but a badly injured horse has to be put to sleep. Fearing punishment, Jamie decides to run away, until Ben decides to take him on a tour of the Ponderosa, namely to see how others handle their mistakes in positive and negative ways.

An alcoholic woman lashes out at Hoss after his testimony sends her husband to prison. She gets back at him by forcing the big guy to take custody of her young son, Petey. Hoss must decide whether to ask the court to adopt him, or help the mother deal with her alcoholism.

Joe is shot and wounded while he is on a cattle drive in the Nevada desert. Two ranchers find him, delirious from thirst and the heat, and take him to their home to recover. While the ranchers summon a doctor, Joe struggles for life, mumbling incoherently and having surrealistic nightmares about a teepee and a wagon wheel. Ben and Hoss try to dechipher Joe's ramblings to piece together what happened.

Hoss becomes a judge in a contest--he has to pick the perfect/prettiest baby. The parents of the babies nearly all try to influence Hoss, so he has a hard time deciding. There is one quite hilarious part (though odd).

Joe volunteers to help an old lawman escort a slick outlaw to jail, but when their prisoner kills the sheriff and wounds Joe, he must face the task alone.

To help the hapless wife and daughter of a lazy dreamer, Hoss arranges a "fixed" horse race.

The wife of Virginia City's new doctor leaves him, after their son dies in childbirth. The doctor snaps and abducts another woman's baby.

Neta, a teen-age girl who is a friend of Jamie's, witnesses an assault and robbery. The victim - Mr. Trumbull, a man who is about to inherit a fortune - dies. The culprit, a drifter named Griff Bannon, gets a glimpse of Neta and, after fleeing the scene, plots to assume his victim's identity and stalk the witness. Her father, meanwhile, is no help, since he raises her by ""traditional values"" and forbids her to socialize with the Cartwrights. Meanwhile, the imposter - now working for the Cartwrights - begins to track Neta's every move and plans to seal her silence, unless she can summon the courage to tell Jamie and the others about the crime she witnessed and identify the baddie.

A veteran blinded by the last battle of the Civil War, returns to Virginia City, to solve the mystery surrounding who killed his brother.

Jamie and three teen-agers - a girl and two boys - are kidnapped by Doyle, a hardened criminal with nothing to lose, and his gang of outlaws. The desperate outlaws use the youths as bargaining tools to make their escape from a trip to prison.

When Luke Calhoun loses all his money in a stock scheme, he and his daughter Meena stay at the Ponderosa with disruptive consequences. Luke turns the ranch into a casino and Meena continues her frantic search for a husband, where she left off in season eleven's "Meena".

Just as Ben begins to formally adopt Jamie, his grandfather shows up to take him away. Ben tells the gentleman, "He's a young man with his roots in Ponderosa soil. This is the life he knows, the life he loves, the life he wants".

Joe is stranded in the desert when his mare falls and breaks her leg. He falls unconscious from exhaustion and lack of water, and is found near death by a Paiute named Swift Eagle. But instead of saving Joe, Swift Eagle steals his gun and goes back to the reservation. His grandfather, Chief Red Cloud, finds the gun and insists they return it and help the owner. Red Cloud cares for Joe until he gets his strength back and then orders Swift Eagle to take Joe into town. In town, Joe meets the most powerful man there, Frank Ryan, who showers Joe with hospitality. Joe feels indebted to both Red Cloud for saving his life, and to Frank Ryan for extending hospitality in an unfamiliar town. So when Red Cloud challenges Frank to a fight to the death, Joe tries desperately to keep the peace. The reason for the fight? Fifteen years ago, Frank took Red Cloud's warbonnet, and has been proudly displaying it ever since, on the wall in his saloon. Red Cloud, now an old man, must regain his honor before he dies.

While panning for gold on his vacation, Hop Sing meets and falls in love with a shy woman. Their future plans are dashed when a judge confirms what Ben has told Hop Sing: the law specifically prohibits interracial marriages.

Hoss enlists the aid of Judith Coleman, a clairvoyant woman who has the gift of "second sight" to find Jamie. He has been missing in the high country and cannot be found by anyone. Judith's gifted psychic abilities have had a long history of men casting her off as a witch, so at first she is reluctant to help the Cartwrights search for Jamie, then changes her mind since she owes them a great deal. Her fiancee, Jess Avery, who is a minister, doesn't look with favor as to her abilities and she may face the consequences of losing him unless she finds Jamie. Hoss refers to Jamie as his "little brother" for the first time.

Fired ranch hand, Cactus, suggests that Ben is too old to put in a real work's week and challenges Ben to take a job as a ranch hand under the name "Ben Brown". He takes the job to prove himself better than Cactus.

Ben helps shepherd a young family, the Kosovos (Nick; his wife, Anna; and his son, Sandor), who had recently immigrated from Serbia. Nick soon finds he can't handle the pressure needed to become successful in America and, one evening while Ben is visiting, his mind snaps. He goes on a rampage, trapping Ben (who becomes injured) and a terrified Anna and Sandor inside their home. Ben must do all he can to keep Nick at bay and try to reason with the mentally ill rancher.

All about Joe and Hoss' visit to a small Mexican town named Agua Santos, which seems to have some rather peculiar laws. The two Cartwright boys soon find them in pretty deep trouble for breaking ""laws"" that barely would pass without notice stateside.

A band of ex-Confederate soldiers demands $25,000 from Ben. When Hoss resists their demands and tries to fight them, their leader, Shanklin, shoots Hoss in the abdomen. Hoss lingers near death, and when the doctor is unable to complete the surgery, a nearly inconsolable Ben persuades Shanklin (a confident, competent doctor) to save his son's life. Meanwhile, Jamie - who had witnessed the shooting and nearly got shot himself - searches high and low for Joe, who is involved with a beautiful starlet and intently focused on a poker match.

Sid Langley is a real estate broker who is not well liked in Nevada, thanks to his shady ways of doing business. An irritable Ben is barely polite with Langley when closing a land transaction. However, things soon get worse than that headache and blurred vision Ben suffers from when he learns that Langley has been critically wounded by an unknown assailant. Ben, who somehow can't remember the past 24 hours, fears he may have been the gunman and tries to reconstruct the activities of the past day to prove his innocence.

A 7-year-old boy is killed after he walks into a bank during a robbery by the ruthless Springer gang. Joe and Jamie help the boy's angrily grieving grandfather track down Springer.

A comic tale of mistaken identity, as Hoss (and eventually Ben and Joe) are held in connection with a series of road gang robberies by the bumbling Younger Brothers.

The Cartwrights are once again brought in the middle of the Civil War. This time, the wife of former Civil War Col. Cody Ransom brings her young daughter to the Ponderosa, trying to pick up the pieces of their lives. However, Ben soon learns that Col. Ransom may be trying to search for his family. However, Union Maj. Donahue has been pursing Ransom and his men for many years after the war ended, and has refused to accept anybody's terms of surrender - especially since Donahue considers capturing Ransom a personal matter.

Ben's ability to close a lucrative livestock contract with a conspicuous widow hinges on the sale of a dilapidated saloon in Upright that Hoss and Joe had impulsively purchased. However, the boys put off the sale when the town drunk (who acts as ""saloon keeper"") insist the crumbling Trails End Saloon may house a fortune. Things get even more complicated when a woman, claiming to be the daughter of the deceased former owner, envisions turning the Trails End into a booming saloon, hotel and restaurant.

While the Cartwrights are away to Carson City, ruthless land baron Bradley Meredith (Lorene Greene in a dual role) poses as Ben in a scheme to get control of the Ponderosa ... by pretending ""Ben"" is seriously ill and selling his holdings to friends.