Amphibious inhabitants of the planet Aridius. This world used to be covered in oceans, but its orbit brought it closer to its twin suns and the seas boiled away. Now the planet is a desert, and the Aridians live in an underground city. They are preyed upon by carnivorous Mire Beasts. These creatures used to live in the slime at the bottom of the oceans, but now they are breaking into the city. Large sections have had to be blocked off to stop their spread. The Doctor and his companions arrived on the planet and found that they were being hunted by a Dalek death squad, who had a time machine of their own. Some Aridians were forced to dig the TARDIS out after it had been buried by a sandstorm. They were exterminated after they had completed their work. The Daleks then forced the Aridians to hand over the Doctor and his friends. If they failed to do so, their city would be destroyed. The time travelers escaped when Mire Beasts broke into the part of the city where they were being held. They fled the planet in the TARDIS, and the Daleks followed - leaving the Aridians to fight their losing battle against the encroaching Mire Beasts.
Played by: Ian Thompson, Hywel Bennett, Al Raymond. Appearances: The Chase (1965).
- The Aridians feature in the second episode only - The Death of Time.
- Clips from this episode are often shown in those "before they were famous" shows, as Hywel Bennett would go on to have a highly successful acting career.