The search for Susan:
School teachers Barbara Wright and Ian Chesterton's search for one of their pupils, Susan, bring them to an old junkyard. There they meet her grandather, the Doctor, and what looks like and ordinary police box.
The Tardis takes off for first time:
Fearing that his time machine will be discovered if he lets school teachers Barbara and Ian go, the Doctor sets the TARDIS on its first journey. When the TARDIS finally materialises, it is on a barren, rocky landscape, with an ominous shadow falling across it.
The Doctor is ridiculed:
A doubting Ian Chesterton challenges the Doctor as to whether the TARDIS has indeed travelled through time. The opening of the doors of the time machine reveals not the junkyard of 76 Trotter's Lane, but a Palaeolithic landscape of another world.
Where are my matches?:
With the Doctor captive and the tribe arguing and deciding his fate, it seems only his ability to make fire will save his life. But just where has he left his matches!
You must not make fire!:
The Doctor and his companions are fighting to free themselves from the bounds around their wrists when the Old Mother enters the cave. Although brandishing a knife, she is willing to release them on the condition that they do not make fire. But behind the Great Stone, the tribe are trying to break through. Will the Doctor and his time-travelling friends make their escape?
A chance to escape?:
The Doctor and his companions are trying to escape through the Forest of Fear. When Susan stumbles on the carcass of a freshly killed animal, her piercing screams alert Za and Hur and they are forced to take cover. A predator is loose in the forest and when Hur is attacked his anguished cries prompt an compassionate response from the time travelling school teachers.
Kal is banished from the tribe:
The Old Mother has been killed and Kal accuses Za of her murder. As the tribe look on, the Doctor challenges Kal's version of events and is tricks him into revealing his own bloodstained weapon.
Pursued by ancient savages, the Doctor and gang head for the Tardis. But as they disembark at their new point of arrival, the Tardis radiation detector registers 'Danger'