2/7 Looking for Barbara, the travellers realise they have been exposed to radiation poisoning.
BBC Television Service
1/7 The travellers venture explore a new world. Everything seems to be dead, but is it really?
4/4 The Doctor and his companions use guile to escape death at the hands of their captors.
3/4 The Doctor and crew leave the TARDIS to explore their new surroundings, but are captured.