The pilot episode tells the audience the names of the characters of the programme, including the Gog family clan and their main antagonist Ray the T-Rex, in the form of cave paintings. At the beginning of the episode, the Gog clan are huddled together at night on a cold, bleak, windswept landscape. The Gogs are getting up to their usual revolting, uncivilized activities and hitting each other. A freak storm breaks out, terrifying them all, except the crazy infant, Girj, who finds it all amusing, causing the mother Ogla to kick Girj off screen. The storm causes a withered tree to be hit by a bolt of lightning which then sets it on fire, giving the Gogs the inspiration to make fire for the first time. Dim-witted teenage caveman Ogo quickly and unexpectedly turns to scream right at the camera as his hand is burnt by putting it into the fire. As he screams, grandfather Gogas hits Ogo over he head with his club, and the clan go to sleep around the warmth of the fire. They awaken sleepily to a hungry T-Rex named Ray descending on them, and as the Gogs scream and flee they leave behind the teenage daughter, Igi, who is almost eaten. Ogo saves the day when he holds a flaming torch to Ray's private parts, causing Ray to dart off quickly in pain. As Ogo basks in his clan's praise, he quickly loses it again as he blows the flame out, which was the last remnant of the fire they had, and as such the secret of fire is lost. The rest of the clan beat up Ogo for this, and the next night they remain cold without fire like the night before.

The second episode begins with Ray the T-Rex still searching for the Gogs, his pride (and private parts) wounded. Meanwhile, the Gogs have moved from the barren windswept plateau to a lush, bright, and gargantuan-sized primeval rainforest buzzing with all manner of bizarre flora and fauna. Baby Girj is having a tantrum, screaming and pooing and weeing on the forest floor, causing the rest of the clan to shove rocks in their ears to drown out the sound, and vomiting at the stench. Mother Ogla wipes Girj's bum on a banana leaf, and then throws it in husband Oglas's face. The day consists of many similar antics, until grandfather Gogas comes up with the idea of building Stonehenge. The plan collapses when a giant, prehistoric forest spider latches onto Oglas' face, causing him to drop the first stone on his father Gogas. Nevertheless the Gogs persevere, and although dozens of similar mishaps upset the construction, Stonehenge is built – which is in fact revealed to be an elaborate swing to keep Girj happy and stop his tantrums. Although it does indeed keep Girj happy, it nonetheless makes him louder than ever in his excitement, driving the rest of them mad.

As the rest of the family sit around on a plateau, father and son team Oglas and Ogo decide to go on a hunting trip to the rainforest to fetch food for the hungry clan. Not surprisingly, the trip is a disaster full of misadventures, as Oglas and Ogo are not adept hunters. After they leave, a brontosaurus keels over dead next to the rest of the clan on the plateau, who then prompty feast upon it. Meanwhile in the rainforest Oglas and Ogo bump into a red-skinned deinonychus who beats them up with kung fu. They flee, only to bump into Ray the T-Rex, prompting more running. Oglas and Ogo escape Ray by jumping off a cliff but not before losing their clothes which Ray catches in his jaws. They land in the brontosaurus' rib cage and are trapped inside like a prison, naked, exhausted, beaten up and hungry, helplessly looking on at the rest of the clan who are soundly sleeping off their hearty brontosaurus meal.

The clan are sat around on the plateau as grandfather Gogas chases after the mole. Ogo snots everywhere and all over the rest of the clan, and Oglas beats him up for it, and Ogla breastfeeds Girj to stop him from screaming. A windstorm kicks up pace and the clan use giant leaves as a windbreak. Ogo climbs a tree to fetch such a leaf, but at the top of the tree he is attacked by a pterodactyl hiding in the leaves who picks him up with its claws and carries him off. Gogas throws a rock at the pterodactyl, which then drops Ogo down a hollow tree stump. The pterodactyl swoops down on Gogas but Gogas knocks it out with his club, and loses his clothes as he swings. A tornado bears down on the clan, and as they look on in horror, Oglas' brain puts on a hat and vacates his head. Baby Girj escapes by following the mole down its hole. The rest of them take refuge in the tree stump to find a large underground cavern beneath, but Ogla gets stuck in the tree stump. After the mole saves Girj, Gogas again attempts to whack it with his club, but the mole steals the club and hits Gogas with it.