Alpha Centauri

Alpha Centauri was an alien from the planet Alpha Centauri near the star of the same name. I think it's adrodgynous, it's been so long since I saw those episodes.
Alpha Centauri was ambassador to the planet Peladon, and aided the Third Doctor against the bad guys.
It also has the distinction of being the first character I remember, other than the Third Doctor, from when I was a child.
Alpha Centauri was portrayed by Stuart Fell (In the costume) and Ysanne Churchman (As the voice).
Alpha Centauri appears in the Third Doctor episodes "The Monster of Peladon" and "The Curse of Peladon"

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