Tribe of Gum

The Tribe of Gum was a tribe of Caucasian, cave-dwelling humans that lived on Earth in 100,000 BC. They worshipped a sun god called Orb. They were visited by the Doctor, Susan Foreman, Barbara Wright and Ian Chesterton, who taught them to make fire and to show compassion to one and other. The four fled from them in fear from the tribe and dematerialised in the TARDIS. An alien race known as the Prometheans saw this brief encounter, and decided to continue what they had seen as an abandoned social experiment by giving the tribe psychic metal, which granted them god-like powers and allowed them to travel to the stars in search of more metal, as well as the teachers which had left them before.

History
One of the tribe's favoured policies was that leadership was given to the one who was able to make fire. Therefore this ability was a closely guarded secret, and passed only from father to son. However, the last firemaker was killed in a hunting accident before he taught the secret of firemaking to his son Za. Therefore the tribe was freezing during the winter and unable to cook their food, which included tiger and bear. Some of the tribal elders however shunned fire altogether, with one woman stating, "There were leaders before there was fire; fire will kill us all in the end."

Another member of the tribe was an elder named Horg. He was once a great leader, before he got too old. Due to his high status, his daughter Hur was the most prized female in the tribe, and would be given only to the tribe leader. The prospect of Horg's daughter made the position of leadership all the more attractive.

Za wanted to take what he saw as his rightful place as the leader of Gum, but without the ability to make fire, the others would not wholeheartedly follow him. There was an outsider called Kal who had been taken in by the tribe some time ago. He was full of vigour, and some of the people thought he had a better chance of making fire than Za, and so wanted to follow him. Naturally, a struggle for power broke out between Za and Kal.

One day during this power struggle, Kal was out roaming the countryside and came across the First Doctor, who produced fire with matches. He seized this opportunity to knock the Doctor unconscious and haul him back to the tribal caves.

Meanwhile, the Doctor's companions Susan, Barbara and Ian had realised he was missing and were out searching for him. But they too were captured by the tribe and brought to the same cave. The Doctor woke up and offered to make fire for the tribe if they took him back to the TARDIS, where he had left spare matches, but the tribe were so involved in their power struggle that they were unable to listen. During an argument, some of the tribe were going to kill the companions on the spot, but Za prevented this, proclaiming that Orb would wish to see them. He believed that if they waited to sacrifice the quartet when Orb next appeared in the sky, then Orb would grant them fire. Thus the prisoners were taken to await their fate in the Cave of Skulls.

An elder woman, fearing fire, set the captives free in the night. Za and Hur followed them into the Forest of Fear in order to get their secrets of fire. Za was attacked by a beast. The companions nursed him back to health, and the pair were puzzled at this caring behaviour, as killing rivals was the norm in those primitive times. Meanwhile Kal killed the old woman and blamed Za. Led by Kal, the tribe caught up with the delayed travellers. Kal confronted Za, but the Doctor was instrumental in turning the tribe against Kal by tricking him into showing his blood-stained knife, and they drove him away. The tribe, now led by Za, recaptured the companions and took them back to the Cave of Skulls. Za took this opportunity to learn the fire secrets from them. In the midst of this Kal returned, killed the guard at the Cave of Skulls, snuck in and challenged Za. They fought to the death with Za emerging as victor. With Kal dead, and the knowledge of fire in his possession, Za emerged from the cave as the undisputed leader of Gum. Za insisted on a union between Gum and the new tribe of the companions, and would not hear otherwise. The companions thus used their cunning to frighten the tribe and escape back to the TARDIS.

The tribe pursued the companions, just in time to see the TARDIS vanish. (TV: An Unearthly Child)