NYSSA
Nyssa
Nyssa is a fictional character played by Sarah Sutton in the long-running British science fiction television series Doctor Who originating from the planet Traken. Nyssa was created by writer Johnny Byrne for the Fourth Doctor serial The Keeper of Traken, but the production team subsequently decided that she should join the Doctor on his travels. She returned in the following serial Logopolis, in which the Fourth Doctor regenerated, and remained as a companion of the Fifth Doctor. She was a regular in the programme from 1981 to 1983.The above text is a snippet from Wikipedia: Nyssa (Doctor Who)
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