"The Enemy Within" is an episode of Star Trek: The Original Series, and was broadcast on 6 October 1966. It is a first season episode #5, production #5, and was written by Richard Matheson and directed by Leo Penn.
Overview: A transporter mishap divides Captain Kirk into two versions of himself, one good and one evil, but neither is able to function separately for long.
Источник
Далее идет изложение сюжета, который совпадает с Пятой Колонной.
Так что, проверте свои источники.