Koreelya

 was a scientist trying to find a cause for the madness on Tranquela with her partner Ravlos. She was only assigned to the science division. She worked out a way to cancel out the wave. After meeting the Sixth Doctor, she worked out it was the holiday globe that caused the Doctor's madness from the hate ray. Escoval hypnotised her to lie to help in her plans. (AUDIO: The Ultimate Evil)