Perpugilliam 'Peri' Brown played by Nicola Bryant
Peri was rescued by Turlough after jumping into a lake. She travelled with the Doctor for some time before having the mind of Lord Kiv of Thoros Beta replace her own.
Her fate is not properly known: during the Doctor's trial evidence was fabricated. One suggestion is that she was killed by Ycarnos after Kiv's mind was transplanted. The other suggestion is that she was rescued by Ycarnos and now lives as his queen.
She witnessed the regeneration from Peter Davison into Colin Baker.