In Bedrock, a man who bears an uncanny resemblance to Fred Flintstone Alan Reed races through the streets, pursued by Ali Don Messick and his associate, who believe they’ve finally ended Rock Slag after forcing him off a building. The chase sets the tone for a spy-spun adventure that still hums with the familiar stone-age charm. Meanwhile, the Flintstones and Rubbles are gearing up for a camping vacation, which includes dropping off Dino and Hoppy at the veterinarian. On the way home, Fred crashes Barney’s car, and a stop at the hospital reveals that Rock Slag is also recovering. When Ali and the other pursuers locate Rock and knock him out of commission again, Chief Boulder Harvey Korman of the Secret Service steps in and asks Fred to take Rock’s place in a high-stakes Paris meeting.
Thinking this is simply a vacation, Fred tells his family that their trip to Eurock is all-expenses-paid, a playful misdirection that the family accepts with good humor. Barney and Fred decide to return their camping gear and use the money to buy the Rubbles’ tickets, turning the trip into a real international caper. Ali keeps up the pressure, making several attempts on Fred’s life under the assumption that he is Rock Slag.
In Paris, the Chief reveals the mission’s real stakes and sends Fred to Rome with the help of Triple X, the master of disguise. Fred’s path crosses Tanya Malichite June Foray, the glamorous and formidable #1 female lieutenant of the master criminal known as the Green Goose, who has agreed to surrender the Green Goose in exchange for a chance to meet Rock Slag. Fred’s thoughts keep returning to Wilma Jean Vander Pyl as he tries to balance his cover with the pressures of the mission, and he finds himself dodging an array of admirers linked to Rock Slag as the evening unfolds.
After a failed attempt to keep his distance from Wilma, Fred buys her a “genuine imitation diamond necklace” from a street hustler to smooth things over, only to discover that Wilma slept through the night, unaware of his absence. Fred’s curiosity about the Chief’s hidden office grows, and discovering it deepens his dilemma: backing out could jeopardize Pebbles’ future, so he makes a loose excuse to meet Tanya at a restaurant. Wilma and the Rubbles arrive at the same spot, catching Fred and Tanya together and assuming the worst. Rock Slag arrives to take Fred’s place, but Wilma, Betty, and Barney mistake him for Fred and pound him, leaving him out of commission again.
Tanya guides Fred toward the Green Goose’s hideout, located in an abandoned amusement park, but the Chief has already fallen to Ali and Bobo, leaving Fred without back-up. Barney trails Fred but ends up captured, enduring torture in a bid to extract Fred’s “Rock Slag” secrets. Fred refuses to talk, holding to his integrity even under pressure.
Triple X is revealed to be the Green Goose, who plans to launch a deadly inter-rockinental missile disguised as a park ride. Fred and Barney accidentally lock themselves inside the missile, and the Green Goose, thinking they carry a priceless necklace, opens the door to bargain for it. Seizing the moment, the duo overpowers their captor and locks the Green Goose, Ali, and Tanya inside the missile, which is redirected toward outer space to an unknown fate.
Back in Bedrock, a grand welcome home greets Fred, now celebrated as a hero, though he remains grateful simply to be with his family after resolving the restaurant misadventure. The family heads off on a quiet getaway, but the ending brings a familiar wrinkle: Roberta Janet Waldo and her brother Mario appear and pursue Fred, whom they mistake for Rock Slag, creating a finale of comic confusion for Wilma, Barney, and Betty Gerry Johnson.
