Rancher Ralph Lamb is tasked with bringing order to Las Vegas in the 1960s when Las Vegas is swelling with outsiders and corruption which are intruding on his simple life. Recalling Lamb's command as a military police officer during World War II, the Mayor appeals to his sense of duty to look into a murder of a casino worker -- and so begins Lamb's clash with Vincent Savino, a ruthless Chicago gangster who plans to make Vegas his own. Assisting Lamb in keeping Law And Order are his two deputies: his diplomatic, even-keeled brother Jack and his charming but impulsive son, Dixon. Ambitious Assistant District Attorney Katherine O'Connell, who grew up on the ranch next to the Lambs, also lends a hand in preserving justice. In Vegas, two powerful men -- Lamb and Savino -- are engaged in a fierce battle for control of the budding oasis, and for both of them, folding is not an option.
When Sheriff Lamb investigates the death of Porter Gainsely's attorney, it triggers retaliation attacks that puts Katherine in the hospital and leaves Lamb without a badge. Meanwhile, Sheriff Lamb also discovers new details that could reveal the truth behind his wife's untimely death.
Lamb, Jack and Katherine take advantage of the phone tap in Savino’s office and try to get evidence on how Savino works the skim, making District Attorney Reynolds very nervous. Meanwhile, Dixon and Yvonne arrive in Los Angeles to visit Violet at a movie studio, and Yvonne finally gets the chance to show off her beautiful singing voice at a big Hollywood party. Also, Mia is shocked when her presumed dead mother, Lena, arrives at the Savoy and sets her sights on Savino.
As Sheriff Lamb and Jack investigate the murder of a Savoy craps dealer, a desperate suspect in the case takes Mia hostage, demanding a ransom for his getaway. Meanwhile, Savino plots to play dirty with Gainsley when The Tumbleweed Casino reopens, and Yvonne questions her new relationship with Dixon when her ethnic background becomes an issue.
Sheriff Lamb needs to find a way to help his son when Katherine arrests Dixon after a bruised Violet accuses him of assaulting her. Meanwhile, Savino has his own problems when Lena finds a gambler’s body in one of the Savoy’s suites.
Sheriff Lamb and FBI Agent Byrne butt heads when Byrne prevents Lamb from pressing charges against a pimp in order to get info on Savino instead. Also, Dixon falls hard for Hollywood starlet Viola, and Tommy and Dixon discover that Yvonne has a chance at becoming a professional singer.
Jack is in dire trouble when he’s blindsided by Mia’s father, Rizzo, who wants to grill him about his daughter. Meanwhile, Dixon saves a drowning girl and discovers she was poisoned, and Savino and his Savoy crew find themselves stranded in the desert overnight.
Savino decides it’s time to put a new, mob-friendly mayor in office, and with his wife Laura’s help, grooms George Grady for the campaign. Meanwhile, Sheriff Lamb investigates the murder of a dentist who appears to have been killed because of his gambling addiction.
Sheriff Lamb suspects Savino of kidnapping the son of a member of the Nevada Gaming Commission in order to fast-track a gaming license for The Tumbleweed. Meanwhile, when Savino's wife, Laura, comes out to Vegas to support him in a new venture, his promise that their family will be safe there is put in jeopardy when a ruthless hitman from Milwaukee arrives in town.
Rizzo complicates life for Savino when he hires a popular singer at the Savoy who is also Savino’s ex-mistress, Diane Desmond. Meanwhile, Ralph, Jack and Dixon share jurisdiction with the military on a murder case when clues lead them to a nearby Air Force base.
Sheriff Lamb assigns Dixon an undercover job at the Savoy when Savino suffers a series of robberies, while Ralph and Jack look at the mob when they investigate the murder of the biggest contractor in Las Vegas.
When a young Vegas showgirl is attacked and murdered, the Lambs work to track down the killer, realizing early on that there’s something about the case that resonates personally with Katherine. Meanwhile, Savino manages to land a high roller at the Savoy and tries to use him to show other “whales” that the Savoy is a real contender for high stakes gambling.
When Savino tries to invest in the same casino that the local Milwaukee crew has been eyeballing, Milwaukee comes after him. Meanwhile, when Sheriff Lamb investigates the murder of an African American maid, he's surprised to uncover her connection to one of the town's most wealthy businessmen.
Sheriff Lamb is kidnapped by a suspect bent on revenge, and is forced to dig his own grave. Meanwhile, Savino and Rizzo are roughed up by a rival mob and must come up with a deal quickly to try to save their lives, and Katherine and Laura embark on a new partnership.