They're saved and taken in by one family, composed of Gara and Gorok, their teenage son Lok, their little girl Tana, and their baby pet Stegosaurus Glump. Together, the Butlers learn the ways of these people while constantly trying to leave the valley and return home. Each episode, the cave people face some problem that threatens the valley, be it dangerous animals, neighboring tribes, or natural disasters. The Butler family will often help solve these problems by using modern tools, such as a catapult, that the cave people haven't discovered yet. Sometimes though, the cave people's methods work just fine.
See also Dino-Boy, an earlier Hanna-Barbera series with a similar premise.
This series provides examples of:
- Action/Adventure Series: One of Hanna-Barbera's only 1970s shows to be in this genre, as most of their 1960s adventure series had ended due to complaints from Moral Guardians.
- All Animals Are Dogs: Glump acts more like a dog than a Stegosaurus.
- All Cavemen Were Neanderthals: Zig-zagged. While some of the valley people such as Gorok's family appear to be quite accurate Neanderthals, the other tribes do not look much different than modern humans.
- Artistic License – Paleontology:
- The pterosaurs, while fairly accurate for the time, are portrayed as bipedal.
- The Brachiosaurus in "A Turned Turtle" has a diplodocid-like body, despite being famous and named for having longer front legs than back.
- The Tyrannosaurus and Allosaurus both have one finger too many.
- Brains and Brawn: The Butler family and Gorok's family, respectively. Not that the cave people are dumb by any means, but they're just very underdeveloped compared to the Butlers, and therefore rely more on brute strength and street smarts to live.
- Brandishment Bluff: In "Rain of Meteors", the Butlers and Gorok's family accidentally injure a passing hunter from a neighboring tribe with their catapult. The hunter's father turns out to be the chief, and takes it as a deliberate act of war. When Lok and Katie go over to explain, he holds them hostage. However, this tribe believes in a sky god, and fear meteors. So the Butlers and Gorok's family tells them that if they don't release the pair, they'll tell the sky god to send meteors (actually flaming rocks launched from the catapult).
- Chew-Out Fake-Out: At the end of "Forbidden Fruit", Greg thinks Gorok will punish him for stealing some fruit that was intended to pacify a Brontosaurus. Instead, in a weird example, Gorok throws Greg onto the shoulders of Lok, smiling, and everyone laughs.
- Clear My Name: In "Top Cave Please", Katie, Greg, and Tana set out to prove Lok's innocence when he gets framed for a crime he didn't commit.
- Cruel Elephant: An aggressive mastodon threatens the cast in "Test Flight".
- A Day in the Limelight:
- "Glump in The Saber Tooth Kids" after falling down a hole. Tana spends the whole episode worrying and mounting a rescue.
- Lok in "Top Cave Please". He is falsely accused of setting free a dinosaur that supposedly brings good luck to the cave hunters.
- Deadpan Snarker: Katie, constantly in the form of witty one-liners. The other Butlers do this, too, but Gorok and his family seem to have no concept of sarcasm.
- Fight to Survive: Every day is like this for Gorok's family and the other tribes, since they're all very primitive civilizations, and they live in a place where Nature Is Not Nice. The Butlers only experience this once they fall out of their boat and into the valley of the cave people.
- Frazetta Man: The main threat of "Smoke Screen" are a troop of aggressive half-human primates known as the Geebos, provoked when their leader gets ensnared by a trap the Butlers built.
- Good Parents: Both sets of parents are always looking out for their children's safety, especially since they live in a place where Nature Is Not Nice. One particularly awesome moment is when Lok is falsely accused of a crime and put on trial. Gorok and Gara are very upset, and you can hear it in their voices.
- Heel–Face Turn: Any enemy tribe of the valley people will end up making peace with them, due to the Butlers' influence.
- Heinous Hyena: In "Pteranodon", a pair of cave hyenas threaten to eat the medicine for curing Kim's sickness, and they are driven away by the younger kids and pets.
- Herbivores Are Friendly: Subverted. While most of the herbivorous fauna in the valley tolerate the humans and are docile if left alone, quite a few of them are territorial or protective of their food supply. Some episodes feature Triceratops, mastodons, and Megatherium acting aggressively for some reason or another and in a couple of episodes, Brontosaurus and Iguanodon are outright MOTWs. "Torch" features a Styracosaurus that's only aggressive because she's a mother missing her young, and she immediately leaves the humans alone once they return her young.
- Hollywood Prehistory: Played with. The valley people and the neighboring tribes all seem to live this way, complete with dinosaurs and other pre-human animals running around. However, except for the pre-human animals and the fact that everyone speaks English, it actually depicts early cave people rather realistically, from the way they look and dress, to their government and lifestyle. The valley people and neighboring tribes actually seem to be living like how many Native American tribes once did (besides the whole living in caves thing).
- Hollywood Science: Averted. When science is used or discussed, it's surprisingly accurate. About the only major thing that stands out against this was polishing a turtle shell to be transparent.
- The Horde: A pack of Allosaurus is the main threat of "Rain of Meteors".
- Horrifying the Horror: Even the Tyrannosaurus flee from the giant army ants in "What Goes Up".
- Lean and Mean: Bork, the man who released Rocar and let Lok take the blame in "Top Cave Please". For once, a justified example, since it is implied that he is scrawny because he can't hunt very well, and he is angry that he will not be allowed on the hunt which means that he's mean because he's lean.
- Lost World: The setting for the series is somewhere in South America, where many animals otherwise thought extinct still exist.
- Nature Is Not Nice: The cave people, the Butlers, and all the other tribes have to share the land with not only dinosaurs of all kinds, but also with saber tooth cats, dire wolves, terror birds, various other dangerous animals, and somehow even dangerous flora.
- Native Americans: Besides the dinosaurs and the living in caves, there are many parallels between how the cave people society and how many tribes of the United States once lived, especially the Plains tribes.
- Never Smile at a Crocodile:
- A crocodile menaces Lok and Katie in "Pteranodon".
- In "Aftershock", Greg unwittingly leaps onto the back of a crocodile, which shakes him off.
- In "Torch", while Lok and Katie are running from the mother Styracosaurus, they are cut off by a river infested with crocodiles.
- Not What It Looks Like:
- The Butlers and Gorok's family are testing out a catapult that the Butlers built. They accidentally hit a passing hunter from a neighboring tribe, knocking him off the cliff and injuring him. The kid is fine, but his father turns out to be the chief of the tribe, who sees this as a deliberate attack.
- Another episode has a disgruntled caveman set free a Stegosaurus that is meant to bring good luck to the hunts. Lok, who makes it no secret that he thinks the dinosaur should be free and that hunting success is all about skill, not superstition, is seen at the Stego's enclosure trying to keep it closed. Said caveman falsely accuses Lok of the deed, causing him to be put on trial for it.
- Panthera Awesome: A family of Smilodon are the main focus of "The Big Toothache".
- Raptor Attack: Zig-zagged. While no dromaeosaurids ever show up since they haven't been made stock yet, the series does have Archaeopteryx usually playing the role of Disturbed Doves.
- Savage Wolves: In "Saber-tooth Kids", Glump is menaced by a pack of dire wolves, which Greg and Tana drive away by wearing a Machairodus pelt and pretending to be a live one.
- Shown Their Work: While the dinosaurs are still based on pre-1970s portraits, they are portrayed as being rather lively and quick-footed. Noteworthy as the series was made during the first stages of the Dinosaur Renaissance.
- Spock Speak: The various tribes of the valley all speak this way.
- Stranded with Edison: The Butlers, a family from modern times, are stuck in a valley full of various tribes of people living how early humans did, and surrounded by dinosaurs and other animals. Oddly enough, this doesn't seem to be a case of Trapped in the Past, since in one episode, an airplane flies over the valley but doesn't register anything, making it more an example of Lost World.
- The Swarm: The colony of army ants in "What Comes Up".
- Terrifying Tyrannosaur: Tyrannosaurus (called the "Conga" by the cavepeople) are recurring threats to the protagonists. "A Turned Turtle" features a particular Tyrannosaurus named Godon, called by John as "the granddaddy of the Tyrannosaurus".
