5 – The Enemy Within

Grade: B-

The Enemy Within (1966) on IMDb


Captain Kirk has been on a planet with the specimen-gathering team. After his apparent successful transport back to the ship, a duplicate Captain Kirk materializes on the transporter pad. The original Kirk is passive, and the duplicate Kirk is aggressive.


This is the first of the “Transporter Accident” episodes that became so common in this franchise. It seems every series has at least one such episode, and sometimes multiple versions of the story. TNG probably had about a half-dozen such episodes. Some of these episodes are better than others, as you might expect. The Enemy Within is one is not one of my favorites, but there are some pretty interesting points. I liked what Spock was saying about the need to have both a passive and an aggressive side.

During the events of the episode, Good Kirk finds it increasingly difficult to make any decisions. There’s a scene when Spock and McCoy are talking to Kirk and trying to get him to decide if he should go back on the transporter pad and try to reverse the problem. Yet Kirk can’t make a decision and keeps going back and forth after everything they tell him. It’s pretty funny, in a way.

I’m not a huge fan of William Shatner, and I don’t think he’s a tremendous actor or anything. But he did pretty well in this episode playing two interesting roles.

I sometimes wonder why they didn’t just use a shuttle craft and pick up the landing party. But I don’t think they had one yet. Up to this point in the series, they had only used the transporter. In fact, when this series was created, they originally came up with the idea of a transporter because it would have been too expensive to film a shuttle craft landing on a planet. So I don’t fault them for not thinking of using a shuttle craft during this episode.

Of Note

The good Kirk actually puts on a green uniform so that the audience can more easily tell the difference between Good Kirk and Bad Kirk. One other interesting note is that Bad Kirk actually transports onto the ship facing the opposite direction. It’s an interesting touch. But there is one mistake in this episode. Toward the end, the scratches on Bad Kirk’s face are on the opposite side as before.