Fred Flintstone [Jeff Bergman] promises his wife Wilma Flintstone [Tress MacNeille] they will take a vacation, but he plans to ask for days off and some cash from his boss, Mr. Slate [John O'Hurley], who is also bringing in a distant relative named John Cenastone [John Cena]. After a rocky start, Fred is saved by Cenastone, yet the relief doesn’t come with an immediate payoff or a clear way to break the news to Wilma. Undeterred, Fred grapples with the problem of money and time off, trying to figure out a way to fund a getaway without losing face at home.
At a fair organized by the Lodge of the Water Buffaloes, Fred conceives a high-energy plan to earn money: he enlists Hoppy [Eric Bauza], the hoparoo pet of his buddy Barney Rubble [Kevin Michael Richardson], to challenge people to boxing matches. The fair also features the Boulder Twins, who run a kissing booth and spark jealousy in Wilma and Betty. Hoppy defeats many contenders, but his streak ends when a ruffian named CM Punkrock [Phil Brooks] humiliates him. Angered, Barney steps up to challenge Punkrock and defeats him, driving Punkrock away with his teammate Marble Henry [Mark Henry]. Fred’s eye for opportunity grows; he sees wrestling as a way to multiply profits after Barney’s success.
The crew is soon greeted by a seafood seller named Mr. McMagma [Vince McMahon], and Fred decides to stage an event at an abandoned circus. Fred asks Cenastone to recruit more wrestlers, and Cenastone brings Rey Mysteriopal [Óscar Gutiérrez], a masked clerk, along with The Undertaker [Mark Calaway], a somber gravedigger by reputation. The crowd fills with anticipation as Cenastone and Mysteriopal begin their match; they fight on friendly terms, and the bout ends without a decisive winner, nudging Fred toward a rematch plan. Fred then decides that Barney should wrestle against Undertaker, but Barney protests, only to be pressured into the bout by Fred.
Just as Barney looks poised to win, Wilma and Betty arrive and scold their husbands for risking everything. The tension softens as the situation is resolved with Fred having earned enough money, but the spark for more remains alive. Fueled by McMagma’s bold push, Fred schemes for a second, bigger event and rents Bedrock Stadium for a grand rematch between Barney and Punkrock. Punkrock accepts, and Fred also enlists Marble Henry and the Boulder Twins for the show. Barney refuses to participate, and Fred heads out ahead of him to kick off the spectacle.
Mysteriopal and Cenastone clash again, but the crowd cheers louder for Barney, leaving Fred to announce that Barney will not fight. The others retreat, disappointed that Fred’s plan appears to overlook his friend. Undeterred, Fred steps into the ring to face Punkrock and his allies, but the gauntlet proves brutal. Seeing his friend in danger and inspired by Barney’s stubborn loyalty, Barney decides to join the battle, rallying other wrestlers to participate. Wilma [Tress MacNeille] and Betty [Grey DeLisle] lend their voices to the crowd’s momentum, even as Bamm-Bamm [Eric Bauza], Barney and Betty’s son, joins in to help, defeating Marble Henry with surprising ease.
In the end, the duo’s team triumphs to a roaring reception, and Fred, wiser from the experience, chooses to step away from wrestling on the big stage. He cashes out his profits and sells the plan to Mr. McMagma, realizing the venture has run its course. The finale finds the Flintstones, the Rubbles, and their assembled wrestlers enjoying a well-deserved vacation together, cherishing the renewed harmony and the memories they created along the way.
