In this season of change, Bo and Luke leave Hazzard to pursue careers on the NASCAR circuit. Thinking no one named Duke is available to stop him, Boss unveils his secret weapon: the Mean Green Machine, a large tank that his henchmen plan to crash into banks to set up armed robberies. After Coy and Vance - arriving in town for what will turn out to be a temporary stay - have an all-too close encounter with the tank, they go to Boss and Rosco to demand answers, but Boss professes his ignorance of the situation. Also in this episode, Enos returns to the Hazzard County ...
Boss sells a worthless piece of property to the Dukes' friends, newlyweds Jeb and Carrie Morton. Coy and Vance learn Boss' true motives and - aware the Mortons had been pressured into buying - announce that gold has been found on the property.
Rosco learns he's been nominated for "Lawman of the Year" and - recalling his origins as an honorable sheriff - refuses to play along with Boss' scheme to rob a jewelry store and pin the blame on Coy and Vance.
Truck drivers Coy and Vance are hijacked while delivering a shipment of antiques to Hazzard. A pretty tomboy named Bobby Lee is a stowaway on the truck and witnesses the crime. She escapes to the Duke farm, where she develops a huge crush on the much-older Coy. Coy learns Bobby Lee is an orphan and helps her deal with her insecurities, all while trying to assist Vance in breaking up Boss' scheme to sell antiques on the black market.
When Boss betrays the trust of county administrators from neighboring counties, he takes refuge at the Duke farm. Vance agrees to secretly tape record the other bosses meeting to take to the authorities, before the bosses exact their revenge.
Boss hurriedly puts aside his criminal activities when he learns his father, the supposedly honest Big Daddy Hogg, is en route to Hazzard for a visit. But Big Daddy knows more than he's telling when he claims he was robbed.
Crooked state Senator Maynard becomes aware someone had witnessed him stealing public funds. That witness - Vance's old girlfriend, Jenny - flees to Hazzard, knowing that Maynard's mobster associates plan to kill her before she can approach the authorities.
Boss and Rosco set up an illegal horse betting parlor in neighboring Rapahoe County and makes a fortune swindling money from its patrons. They route the phone calls through the Duke farm, knowing that the authorities will probably investigate and file charges. But Boss doesn't count on new Rapahoe County Boss "Big" Billie Tucker wanting the money, any way she can - nor the Dukes ingenuity. The Dukes catch on that Boss knows the outcome of the races ahead of time, then rigs the odds to wipe everyone out.
Enos' footlocker from the Los Angeles Police Department arrives in Hazzard; unknown to the deputy, it comes complete with some valuable emeralds. Robbers Burke and Carter, who had stolen the jewels years before, become aware that the booty is in Hazzard and are determined to get back the emeralds any way they can.
Boss' latest scheme involves selling phony insurance policies, whereby the survivors of the deceased ostensibly would be paid $100,000. Con artists Ward and Lavina buy one of the policies, then stage a phony accident to cash in. The Dukes' investigation becomes complicated when a shaken Coy believes he caused a fiery accident that supposedly led to Ward's death.
When Boss is unable to convince the Dukes to sell the General Lee, and an attempt to steal the car fails, he approaches Uncle Jesse to play a game of pool. Jesse agrees to wager the General Lee, but then Boss fakes an injury and sends professional pool player Chickasaw Thins in his place.
Boss has Coy, Vance and Daisy detained in Chicasaw County for robbery, so he and his henchmen can proceed uninterrupted in their search for $5 million in stolen bonds, which he had submerged several years earlier at the bottom of Soggy Marsh.
Hughie Hogg returns, with his eye on the office of Hazzard County Sheriff. He blackmails his Uncle Boss into supporting his campaign by threatening to take secretly taken photographs of his criminal activities to the FBI. Coy and Vance decide to support incumbent Rosco while they collect enough evidence to derail Hughie's campaign and run him out of town.
Hatfield and his new partner-in-crime, Baxter, return for a rematch of their Mean Green Machine vs. the General Lee. This time, Hatfield plans to rob the Hazzard Emporium out of millions in gold. When the giant tank develops mechanical failure, they hold Cooter at gunpoint until it is repaired properly ... or else.
Boss' old moon-shining rival, Floyd Calloway, is out of prison - and he's not happy. He plans to exact murderous revenge on Boss, because it was his testimony that sent him to away. Boss appeals to the Dukes for help, but know that - because Calloway is well-armed and has plenty of help - he can run for only so long. So, they decide to stage a phony funeral for the dearly departed Hazzard County Administrator - unknowing that Calloway plans to come to Hazzard ... and it isn't to pay his respects to the Hogg family.
Coy's new relationship with a motorcycle stuntwoman creates dissension in the Duke household when Vance suspects that her sideshow has been involved in a string of armed robberies. Coy decides he doesn't have to take Vance's warnings and moves out, leaving Vance and Daisy to uncover the truth and make Coy see that beauty is only skin deep.
Uncle Jesse is a customer at the Capitol City Jewelery Store when it is robbed by two hooligans named Parker and Hanson. Jesse tries to subdue one of the robbers, but is given a concussion that causes him to lose his sight. Jesse is otherwise unhurt and is soon allowed to go home. The only problem is, the Duke cousins want to go after Parker and Hanson, who are still at large. So, they convince Boss to let the Duke patriarch stay until they are brought to justice, knowing that the blinded Jesse will helpless should Parker and Hanson get to him first.
Bo and Luke arrive home in Hazzard - just in time to learn that Boss plans to foreclose on Cooter's Garage, purportedly for owing back mortgage payments. The Dukes quickly learn that Boss really plans to build a shopping center and that Cooter's property is key in making it a reality.
Bo and Luke join the Big Brothers-Big Sisters of America, and take budding juvenile delinquent Andy Slocum under their wing. After Andy's attempt to steal the General Lee fails, Bo and Luke are determined to point the young lad in the right direction. A syndicate crime boss also hopes to exert his influence on Andy, in order to carry out his crimes, then leave the youth to take the fall.
Boss conspires with developer L.S. Pritchard to acquire the Duke farm and several adjoining properties. However, even Boss doesn't know Pritchard and her cronies plan to engage in strip mining and eventually render all the land in Hazzard useless for farming.
Daisy quickly tires of her cousins' well-intentioned over-protectiveness and, in order to declare her independence and get some much-needed personal space, moves into an apartment with her friend, Sally Jo. Meanwhile, the Beaudry clan try to swindle Boss in a crooked deal and are thrown out of the Hazzard County Courthouse. On his way out of town, Pa Beaudry - wanting to find a naive bride for his son, Milo - spots Daisy and has her kidnapped for a shotgun wedding. Bo and Luke team with rivals Boss and Rosco to race to Daisy's rescue before the preacher can complete ...