Samantha Crawford is a con artist employed by George Cross. Cross once lost $50,000 to Bret Maverick and is determined to get it back. Two riverboat owners staked Maverick $5,000 which he promptly loses to Samantha. Samantha claims Cross is her father and needs the money to get out of jail. Maverick forms a partnership with Samantha and purchases gambling equipment in a scheme to put Joe Riggs, a crooked game room owner, out of business. Samantha and Cross doublecross Maverick by selling the equipment to Riggs.
Bret Maverick suspicions are aroused when he is forced to leave Ten Strike, New Mexico. Determined to stand his ground, Maverick stays in Ten Strike long enough to uncover a bizarre plot of murder and blackmail. Two gunmen, Vic Nolan (Adam West) and Eddie Burke (William Gordon), try to scare Maverick out of town.
Beau Maverick (played by James Garner), father of Bret and Bart announces that he is getting married. The Maverick boys discover that the marriage is a business arrangement, not a love commitment. The young girl, Josephine St. Cloud is being forced by her father to marry the older Beau Maverick. The brothers set out to sabotage the wedding plans, not knowing that Beau Maverick already had a plan.
Bret Maverick falls for a soft-spoken girl, Modesty Blaine (Mona Freeman). They enter into a partnership to sell cats to a mining camp overrun by rats. But rumor has it that most men lose either their lives or their money when dealing with this young beauty. However, Bret stands to lose both his life and his money, so he plots to save both.
Bret Maverick runs into a notorious bunch of bank robbers; Cole Younger, Billy The Kid, Sam Bass, Jesse James, Frank James, Jim Dalton, Black Bart, Ben Thompson and Belle Starr. The outlaws believe that Bret is the infamous Foxy Smith, a well known bad guy. When the outlaws discover Bret's true identity, they force him to do the robbery in Denver. Bret ends up in a mint of trouble.
When George Henry Arnett hears that Bret Maverick is in town to collect his money, Arnett (Adam West) starts a "top gun" rumor about Bret. After he creates a smoke screen, Arnett creeps out of town. Maverick is idolized by the town youngsters, sought after available women and hunted by the town bounty hunter. Bret Maverick is the talk of the town.
Bret is hired by a weathly texan to save her brother Mark from a conniving woman named Melanie. Posing as a Texas Colonel, Bret realizes that he's up against a master crook. With Mark's help and brother Bart's arrival as a weathly Easterner, they set up a scheme to catch the girl and almost outsmart themselves with their own cleverness.
After saving Bret's life, Johnny Rain (William Reynolds) is arrested for robbing a stage coach. While Bret goes to his rescue he becomes ensnarled in a plot that involves a case of split personality - a dance hall wench and a mild-mannered tinhorn gambler who likes to leave 'em laughing... with hysteria.
Bart Maverick wins big, when he wins the "Lucky Lady" saloon in a card game. When Bart goes to Santa Leora to stake his claim, a beautiful Marquesa refuses to relinquish the property to him. Maverick encounters hurling knives, flurry of bullets and pounding fists when he tries to hold onto his newly acquired saloon.
Bret is one of the seven owners of a Riverboat who start down the Mississippi for Memphis to sell the broken-down craft, but soon, in a deadly game of 10 Little Indians, one owner after another is found mysteriously dead. It becomes apparent that if the boat does reach Memphis, it's almost certain it will have but one owner.
Bart Maverick is running for office, he is a sure candidate for U.S. Senate. Bart's political ambition has some town's people out for his blood. His opponents will go to any length to stifle his political aspirations; they threathen his life. Fearful of his opponents, Bart finds a way out of the election, without letting the voters down.
Beau Maverick wins ownership of the Silver Hill, a worthless ore mine. A crooked railroad agent named Shanks tries to cheat the townspeople out of their land by offering them a price that is well below market value. Beau convinces the town to relocate Silver Hill to a sheep ranch twenty miles away. The plan backfires when a new vein of silver is discovered in the supposedly worthless Silver Hill mine, thus enabling Shanks to claim the land without cost. The only hope is for the town to relocate back to Silver Hill before the railroad takes over the land.
On their way to Denver, Beau and Bart Maverick pick up $6,500 in a poker game at Stop Gap. They decide to wire the money to Denver through the Hulett Telegraph Company. They discover the company is a fake and that the telegraph line leads to a cave two miles away where the crooks stash the customers' money and send phony messages in return. The cousins devise a scheme to recover the money and put the company out of business.
In St. Joseph, Missouri, Beau Maverick wins half-ownership of the Golden Wheel Casino. The business venture is short-lived when his partner, Rand Storm, is shot to death by Flo Baker. Storm was a notorious ladies' man and Flo, a female entertainer, was resisting his advances. Just before he dies, Rand tells his younger brother, Luke, that the shooting was an accident. But Luke has Beau framed for murder so that he can take over the business.
Two Army shopkeepers, Marsh and Lawson, have been cheating the local Indian tribes by supplying them with faulty or inferior goods. When one of the tribeswomen named Pale Moon threatens to report them to the Army Commission, the shopkeepers decide to start a war with the Indians. They know the Army will not investigate the woman's claim if they are at war. Marsh and Lawson murder Pale Moon's brother and pin the crime on the stranger who won $2,500 from them the night before - Beau Maverick.
Beau Maverick befriends a prospector named Ebenezer Bolt. Maverick is unaware that Bolt is the partner of notorious horse thief Benson January. An angry posse mistakes Beau for January and is determined to hang him. A young lawyer manages to halt the proceedings until Maverick can have a trial. Beau's conviction seems imminent when the lawyer locates a notorious "hanging judge" and a woman whose sister was engaged to January identifies Maverick as the horse thief.
Beau Maverick crashes a party in Virginia City thrown by eccentric socialite Kiz Bouchet. Kiz has a penchant for smoking cigars, playing poker, and fighting fires. Recognizing Beau as a fellow free spirit, she hires him to protect her. She believes her life is in danger. Beau discovers that Kiz's cousin Melissa, along with family doctor Pittman and attorney Hanford, are plotting to have Kiz judged incompent so they can split her $2 million inheritance. Beau comes up with a scheme to turn the tables on Melissa.
The Fenians, an Irish Revolutionary Brotherhood, are trained soldiers sworn to free Ireland from British rule. The Fenians have gathered in Dakota City to plan a march into Canada where they want to take hold of a small part of British property hostage in exchange for Ireland's freedom. After England pressures the United States to intervene, Beau Maverick is blackmailed into infiltrating the Fenians ranks by a shrewd Army colonel.
In New Mexico, Beau Maverick is taken for over $4,500 ($4,000 of which belong to his friend Jerry O'Brien) by con artists Warren and Crippen and Warren's granddaughter Rosanne. Beau tries to recover the money and even takes the threesome to court, but they outsmart him every time. Beau is so demoralized by the constant defeats, he believes he has disgraced the Maverick name - until Rosanne tells him that her grandmother was a Maverick.
Beau Maverick wins half-ownership in the Blue Bell Saloon in Arizona. In an attempt to raise funds for the floundering business, Beau and his partner Charlotte become partners with a mysterious gold prospector known only as the Dutchman. Along the trail to Superstition Mountain where the gold is located, Beau, Charlotte, and the Dutchman encounter danger in various forms.
Con artist Ferguson knocks Beau Maverick unconscious during an unsuccessful attempt to hoist a priceless diamond necklace from a French countess. Ferguson claims that the countess' diamond is fake and that he was in the process of replacing it with the real thing when Beau startled him. Ferguson offers Maverick $5,000 to switch diamonds. Beau is being set up for robbery by Ferguson and his equally devious wife.
Outside Denver, Colorado, Beau and his friend, Judge Scott, find shelter during a blizzard at the home of Martha Flood and her niece Sally. Martha and the judge are plotting to institutionalize Sally in order to take over her inheritance. However, Martha's lover, a professional killer named Chet Whitehead plans to kill Sally, the judge, and Maverick.
Beau Maverick stumbles onto the cave site meeting place of five outlaws. They were summoned by a bandit named Jess in order to plan a big job. Mavrick passes himself as the notorious Texas outlaw Red Dog. The outlaws become suspicious of Beau when he declines to join them in a $500,000 bank robbery scheme.
Crusading newspaper publisher Bart? The publisher Bart won the rag from is assassinated and a corrupt U.S. Senator files a $100,000 libel suit against the Chronicle. Luckily, Bart's pal Doc Holiday is in town for a dentists' convention and owes Bart $2000. When Doc brags "I have enough collateral to raise the dead!", Bart feels no compunction in selling ½ the headache to Doc. The senator and his sinister political boss are Ivy Leaguers, so the suave Philadelphia dentist/hired gun will come in handy.
Gambling brothers Bret (James Garner) and Bart Maverick (Jack Kelly) are, as usual, hot on the trail of a fast buck when they find themselves partnered with the eager-but-inexperienced Ben Maverick (Charles Frank, son of their British-born cousin, Beau Maverick.