The Sea of Death:
Ian and Barbara hear Susan's scream whilst exploring the pyramid.
The Velvet Web:
The Doctor and his companions enjoy their hosts generousness. However Barbara awakes from a deep sleep to find the surroundings much changed.
The Screaming Jungle:
Barbara finds the next key but is trapped by a moving idol.
The Snows of Terror:
Vasor traps the travellers in the glacier with the ice soldiers.
Sentence of Death:
Sabetha gives evidence at Ian's trial.
The Keys of Marinus:
The Doctor reveals the location of the final key.