Still hoping to strike it rich during his visit to Los Angeles, Estevan shows a great deal of interest in a young woman when he learns she comes from a wealthy family. Don Alejandro accuses Estevan of only being attracted to Margarita because of her money, but the suitor denies the charges, forcing Diego to dress as Zorro in an attempt to frighten Estevan away.
Aaron Pelser's wagon train came across a pair of young boys on a buck board heading west and invited them to join the train. When he found out that one of the boys was actually a girl and the two claimed to be headed to Yuma to get married, Pelser and his crowd force them to be married in North Fork. The wagon train folks want to throw a shivaree, which may have been innocent enough except for two reasons. The first reason being that the couple does not count it as their wedding because they want to be wed by the groom's father in Yuma. The second reason is that Chet Packard keeps pushing things too far, beyond the spirit of a friendly shivaree.
A desperate department store owner foolishly agrees to a scheme to have her store burned down so she can collect the insurance, but the fiery transaction doesn't go down as planned.
Bret Maverick finds himself caught in a deadly love triangle with a lovely woman (Abby Dalton) and a young gunman (Clint Eastwood).
Trail boss Dolph Quince sends for his friend Matt to help escort his cattle herd into Dodge because he is having trouble with Jayhawkers (Kansas renegades), and he hopes to ease the animosity his men have towards all Kansans.
Estevan again becomes a problem for Diego when he decides to earn some easy money. Los Angeles is preparing for its annual horse race and Estevan would like to win the prize money, but his horse seems unlikely to win. His luck changes when he comes across Zorro's horse, Tornado, grazing in a hidden field, and he captures the animal.
A young Englishwoman is suddenly wracked by dreams of drowning in the ocean. She is stunned when her fiancée tells her that he has prepared a surprise honeymoon trip for them--they're sailing to New York on the passenger liner Titanic.
Abel Goss, the photographer who took Lucas' wedding photograph, is in North Fork doing a portrait of Mark standing in the street. When Goss sees Col. Whiteside and his sidekick Jamison, he recognizes them as the butchers who tortured him and others while he was captive in their prisoners of war camp. When Lucas stops him from killing them, Goss swears to kill those men. Whiteside planned to call Goss out, but he had Jamison shooting from the upstairs hotel window, as his insurance. When the shots are fired, Whiteside is dead, shot in the back, and his gun hadn't been fired. Goss is arrested and at the trial Lucas and Mark have different testimonies. Mark reenacts the scene in the street, and Lucas backs Mark's theory , using the photographic negative Goss had shot of Mark.
Despite his warnings, the media event occurs, and the power cables that string into the craft fully activate it for the first time. Glowing and humming like a living thing, it starts drawing upon this energy source and awakening the ancient racial programming. Those people of London in whom the alien admixture remains strong fall under the ship's influence; they merge into a group mind and begin a telekinetic mass murder of those without the alien genes, an 'ethnic cleansing' of those that the alien race mind considers impure and weak.
When a wealthy woman mistakenly accuses her elevator boy of robbing her, his resulting imprisonment will take her to levels of guilt she never expected.
An old friend of Doc's, a nurse, is visiting and he hopes she will stay around Dodge. In the meantime Matt is worried that an ex-con is gunning for him even though he thought he was innocent five years ago.
Diego's uncle, Estevan de la Cruz, arrives in Los Angeles for an unannounced visit and surprises the de la Vegas when he tells them he plans to be their house guest. Furthermore, he expects them to give a lavish party to welcome him. All of this angers Don Alejandro, but to head off a family dispute, Diego convinces his father that Estevan will leave soon.
Matt Conroy is startled when on their honeymoon his wide-eyed, Louisiana-drawling wife Sally suddenly becomes a determined and demanding woman with no accent who denies even knowing him.
Wes Carney and his wife Clair want to settle down and they figure North Fork might do fine. Wes is a well known gunfighter, who has promised Clair that he would hang up his guns for good. The Carney's want to live a simple, honest life and the Feed and Grain Store, which is up for sale, seems like it might work for them. Carney's reputation and the news that he's settling down brings troublemakers to North Fork. Lucas is the only man willing to stand as deputy with Micah. After Lucas tells the Carney's a story, Clair releases Wes of his promise and the three men take on the troublemakers. After the showdown, Clair announces that Wes will be taking the Sheriff's position he was offered in another town, if it's still available.
Quatermass plans to use an invention of Roney's, an "optic-encephalogram", to see these visions. The device will record impressions from the optical centres of the brain, in effect showing whatever the subject is seeing, hallucinatory or not. He wears the device and goes into the craft, but it is Roney's assistant, Barbara Judd, who is affected most. Placing the device on her, they record what she "sees"—a violent, bloody purge of the Martian hive, to root out unwanted mutations.
Two construction engineers are between more than just a rock and a hard place when one of them discovers the other's violent past during an explosive tunnel blast.
Bret and Bart's devotion to one another is tested when they're offered a deal that can mean $10,000 for one of them, but just one.
A man's house is burned and his livestock killed, but he refuses to identify the perpetrators to the marshal.
It is time to send the tax money to the governor, and Sergeant Garcia has a plan to thwart any attempt to steal the funds during the long journey. He orders the town blacksmith to build a huge iron box that requires a special key to open it. The money will be placed in the box and the key sent to the governor by a separate route.