Mahandra (Prisoners of Fate)
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Mahandra (Prisoners of Fate) was the assistant of Adric Traken. She wasn't comfortable experimenting on convicts. She suggested that Adric should met his mother but in disguise. She later stopped Nyssa, Turlough, Tegan Jovanka and the Fifth Doctor. The Doctor's first TARDIS later took her form. (AUDIO: Prisoners of Fate)