Acolyte (The Face of Evil)

An acolyte of the Tesh became extremely frightened when the lights switched to red, indicating that the failsafe energy supply had been activated. He told Leela that it was "the end of the world", reminiscent of what had happened before "the time of land". Soon thereafter, Xoanon telepathically controlled him, and he attacked the Fourth Doctor and Leela. During the fight, the Doctor threw him into an electrified wall. He died, but his death shorted the walls, making them safe again. (TV: The Face of Evil)