The travellers explore the surface of a new world. Everything is dead, but beyond a petrified jungle they see a metal city which the Doctor is determined to explore. Show more

Looking for Barbara, the Doctor, Ian and Susan learn that they have been exposed to lethal doses of radiation. The travellers are confronted by the city's inhabitants - the Daleks! Show more

Fearful of a Thal attack, the Daleks force Susan to trick the Thals. Realising that the Daleks are planning an ambush, the four travellers try to escape and warn the Thals.

Pretending to be a Dalek, Ian finds that that he is trapped inside the casing. The Doctor, Susan and Barbara have no choice but to abandon Ian as the real Daleks arrive and attack.

Ian and Barbara join a Thal expedition that will penetrate the Dalek city from the unguarded mountains behind it. Their journey is a dangerous one, and not all will survive.

The Doctor and Susan are once again taken prisoner by the Daleks. In the mountains, Ian, Barbara and the Thals must negotiate a vast chasm to reach the city.

The Thals and the time travellers attack the Daleks from all sides as the Daleks start the countdown to release deadly doses of radiation into the atmosphere.

Roy Plomley's castaway is actor William Hartnell. Show more