Alydon

Alydon was a member of and scout for the party of Thals which journeyed to the Dalek city in search of food.

Finding the TARDIS
It was Alydon who first discovered the TARDIS in the Petrified Forest. He left a case of the Thals' anti-radiation drug for the TARDIS crew members and later made contact with Susan, giving her an extra case of the drug and also his cloak. Alydon did not entirely trust the Daleks and gave Susan the second case in case his people's ancient enemies did not share the drug with the time travellers as they had promised. His cloak, being made of non-conductive plastic, proved instrumental in the TARDIS crew members' escape from the Daleks, and thus they were able to warn the Thals that they were walking into a trap, but not before the Thal leader Temmosus was killed.

Alydon succeeded Temmosus as leader as the Thals, but even after this act of vicious treachery by the Daleks, he refused to lead his peaceful people into war against their ancient enemies, arguing that it was war that turned their world of Skaro from a paradise to a wasteland. Alydon was in love with the Thal woman Dyoni, and when the First Doctor and Ian orchestrated a ruse in which they threatened to hand Dyoni over to the Daleks for experimentation, provoking Alydon to fight to protect her, he was convinced that he would be willing to fight for something, and must if the Thals were to escape extermination.

Against the Daleks
While Ian and Barbara led a party of Thals to find a way into the Dalek city via the water supply, Alydon worked with the Doctor to devise a means of disabling the Daleks' surveillance equipment. Although the Doctor and Susan were captured, their plan worked and the Thals were able to gain entry to the city, fighting the Daleks in a pitched battle which ended in victory for the Thals. After the TARDIS departed, Alydon settled into a life with Dyoni as they worked with their people to rebuild Skaro. (DW: The Daleks)

Ian and Barbara later named their son John Alydon Ganatus Chesterton in part after the Thals' brave leader. (PDA: Byzantium!)