The misadventures of two modern-day Stone Age families, the Flintstones and the Rubbles.
Pebbles and Bamm-Bamm develop remarkable musical talent, which is exploited by teen impresario Eppy Brianstone. Soon the tots have no time to their fathers, which prompt Fred and Barney to kidnap them. After a frightening police chase, Fred awakens and realizes the whole episode has been a dream.
When Wilma gets a letter from her mother saying that she is moving in with her favorite son-in-law and his wife, Fred begins refurbishing a dilapidated shack to house Mrs. Slaghoople. But soon Wilma learns that he mother was not referring to Fred, but her other daughter's husband. Fred is delighted, until he realizes how much he spent on the shack.
Through a publicity contest, Wilma and Betty win movie star Stoney Curtis (voiced by Tony Curtis) as a ""slave boy"" for a day. Jealous Fred works him unmercifully, until Stoney offers him a job as his stand-in for a new movie. Fred quits his job and prepares for life as a star, which, of course, is not all it is cracked up to be.
A criminal named ""The Mangler"" vows revenge on Fred, the foreman of the jury (which included Barney) who put him away. When the criminal escapes from prison, the Flintstones and the Rubbles go into hiding. Through a series of mishaps, Fred actually manages to recapture ""The Mangler.""
Hoping once again to strike it rich, Fred buys a circus. When the performers quit, Fred must put a show on himself with the help of Barney, Dino, and Hoppy, which he does successfully--so much that the performers return, and the former owner buys the big top back. To prove he is cured of get-rich-quick schemes, Fred passes up a chance to buy an oil well, which of course pays off.
Samantha and Darrin Stephens guest star from television's ""Bewitched"" (voiced by series star Elizabeth Montgomery and Dick York). Darrin goes boating, while Samantha joins the Flintstones and the Rubbles for a camping trip, which ends up pitting the men against the women. Aided by Samantha's witchcraft, the women manage to out-do the men at every turn.
Fred and Barney discover a visitor from another planet, the two-foot high, green Gazoo, who becomes their servant. An evening out at an expensive restaurant, supposedly with Gazoo treating, becomes a nightmare as the alien disappears, leaving the Flintstones and the Rubbles to wash dishes to pay for the food.
Bored by his company picnic, Fred slips away to take a nap, and awakens twenty years later to discover that Barney has become millionaire B.J. Rubble, and that Pebbles and Bamm-Bamm have gotten married. Upon entering Wilma who is now living alone through Barney's largesse, Fred really awakens and realizes it was all a dream.
When Fred is fired by Mr. Slate for fronting the other employees' list of grievances, he turns to pastry entrepreneur by selling Wilma's gravelberry pies. But soon the couple realize they are spending more in ingredients than they are making in profit. Ultimately, Wilma recoups the losses by selling the recipe to a supermarket tycoon.
A hackneyed spy movie turns serious when the villainous Stonefinger and his henchmen suddenly come to life and begin to menace Fred and Barney. It takes the magical powers of Gazoo to get the situation straightened out.
For his costume for the Water Buffalos' masquerade party, Fred picks a spaceman's uniform. Unfortunately, he goes out on a night when a local radio station has launched a publicity stunt about an invasion by space aliens, a stunt that backfires and creates a panic in the city.
Fred's hopping around and howling in pain after dropping a bowling ball on his foot is mistaken for a new hit dance, the Frantic. Invited on the television music show ""Shinrock,"" Fred comes down with stage fright, until a jab from a misplaced pin gets him hopping and howling again.
Barney is mistaken for the long lost Prince of Rockabia, which seems like good fortune until he learns that the sentence for abdication from the throne is death. The appearance of the real prince releases Barney from his royal ordeal.
Wanting to sneak out of a dinner date with their wives in order to bowl, Fred and Barney ask Gazoo for help. The little green alien creates clones of the boys, so that they can be in two places at once, resulting in the inevitable mix-ups.
Gazoo's bad martial advice not only fails to help Fred and Wilma, it actually leads to their separation. The couple reunite only after they each have nightmares warning them that the other is in trouble.
A mix-up at the pharmacy gives Fred pills that turn him into an ape. Barney is the only one to see this short-lived effect, which makes him wonder about his own health. But when the two dads take their kids to the zoo and Fred ends up in the monkey cage after taking another pill, his problem becomes apparent to all.
Gazoo takes Fred on a trip to the twenty-first century, including a stop at Slate Rock and Gravel Company, where Fred learns that the interest on a $4.00 loan he took from Mr. Slate comes to more than $23-million! Upon returning to the Stone Age, Fred vows to repay the loan immediately.
On advice from Gazoo, Fred and Barney start winning big at the racetrack, and attract the attention of a dangerous bookie named Big Ed. Since he got them into this latest mess, Gazoo comes to their rescue.
Two con artists posing as gold miners sell Fred and Barney phony mine. Wilma and Betty find out and trick the con artists into buying the mine back, but Fred and Barney, convinced of its value, won't sell. Only the threats of the con men convince them to recover their investment and head back home.
Fred refuses to play the lead in the PTA show, ""Romeorock and Julietstone,"" opposite Wilma, so she casts Barney instead. Feigning the mumps, Barney (who is terrible in the part) drops out, forcing Fred to take over. But then laryngitis causes Wilma to drop out, so Barney rushes back in, now playing Julietstone!
Gazoo's intervention allows Fred to be boss of the quarry for the day, during which time he finds out there is more to the position than executive lunches and the feeling of power. At the end of the day, he realizes he would not really want to trade places with Mr. Slate.
Fred is delighted to be invited onto Mr. Slate's yacht, until he learns that he is there to paint it. Asking the Rubbles to join them, the couples start having so much fun on board that they forget the paint job and fail to notice the yacht has broken free and is drifting. Slate charges Fred with mutiny and piracy, but Fred redeems himself when he rescues the visitors to an island (including Slate) from a volcano.
When Fred feigns a headache to get out of violin recital, Wilma invites her old flame Wilbur, who still carries a torch for her. Jealous Fred follows them to a dance, along with Barney and Gazoo. Fred asks Gazoo to change Barney into a dance partner, so he can make Wilma jealous in return.
Performing seal dripper takes a liking to Barney, who soon finds himself involved in a plot to steal the aquatic attraction. The leader of the gang of thieves turns out to be Dripper's trainer, who is tired of the seal getting all the attention.
Fred is mistakenly granted membership to a swanky country club and asks Gazoo to turn him into a gentleman, a plan that involves taking ballet lessons, which makes him the laughingstock of the neighborhood. Finally Fred decides that he and Wilma should be themselves, and together they become the hit of the club.
Fred relives the exciting adventures of his grandfather, flying ace Lt. Rocky Flintstone, and his sidekick Lt. Reggie Vanderrock, whose mission is to rescue the famous spy Mata Harrock from the clutches of Baron Von Rickenrock.