Forty-Two

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Forty-Two was a Kobold from Procyon Two. He and two others, Two and Forty, came to Earth in search of the Third Doctor and Jo Grant.

The Kobolds kidnapped Jo in order to get into the TARDIS. Once inside, however, Two and Forty were accidentally killed by a Doctor-created device that Sergeant Osgood brought into the TARDIS. Forty-Two tried to take over the TARDIS, but Jo distracted him long enough for the Doctor to take him back to Procyon Two. (PROSE: Morphology)