So, here we are, 79 episodes later (80 if you count "The Cage"), the final episode of the legendary Original Series.
As a 'stand alone' episode it is perfectly watchable, but in terms of rounding off the series, it is, rather disappointingly, just a standard episode, which could have just as easily have aired at any point during the show's run.
They knew that it was the end of the series, so it's a shame they didn't come up with a story to round things off more. Sadly, such 'finales' would not generally become commonplace in television until some years later.
Anyway, the episode itself is a fair one. I found the device that Janice Lester used to swap bodies with Captain Kirk to be questionable and not overly convincing, but it is one of those plot devices that I suppose you just have to accept for sake of the story.
Kirk being trapped inside the insane Lester's body, with no-one believing him of what happened, is rather nightmarish. William Shatner gives a reasonable performance of Lester inhabiting Kirk's body and becoming more manic as things go on; as does Sandra Smith, playing Kirk-in-Lester's body (all keeping up here?). The pair capture much of each others character, and as a result pull it off much better than it may have been.
I did find it slightly awkward that Kirk couldn't come up with something that only the close crew would know sooner to prove who he was, but it's all part of the nightmarish scenario. In the end, it is Lester's own insanity that very much ruins her plot.
Incidentally, this is one of the few episodes that doesn't feature Nichelle Nichols as Uhura (the second in a row, as the previous episode, "All Our Yesterdays", didn't have any scenes onboard the Enterprise), with a different communications officer in her place. It's a minor thing, but it's a shame all the main crew weren't here for the final episode.
(Also of note is the late Majel Barrett as the semi-regular Nurse Chapel, who here makes the character's only brunette appearance of the series).
The story moves along well, but I did find the final stages of swapping Lester and Kirk back into their own bodies to be over-simplified and over-rushed, and not as satisfying as it might have been.
Although the broadcast order often different quite a lot from the production order, this was the last episode to be both filmed and broadcast.
"Turnabout Intruder" is, as I say, a perfectly reasonable episode on its own, but it's such a shame that they didn't round the series off more satisfyingly. At least we had the Animated Series, and, ten years later, the beginning of the movies.
-Third season overview-
As I have touched upon on many of my reviews, the third season is widely regarded amongst fans as being by far the weakest of the Original Series. Indeed, it did see a drop in a number of areas, most notably the many intelligent stories that we were treated to over the first and second season. In fairness, not all of the episodes are truly terrible, but I find most of them would have made average 'filler' stories, and the season suffers without having more episodes of real quality to bolster them up more.
And then, there are indeed some truly hideous episodes, such as the infamous "Spock's Brain", and the terrible 'space hippies' episode "The Way to Eden".