#65. The Apple
In case you forgot: The Power Trio plus a few redshirts are investigating an unknown planet. After Spock gets sick and a few redshirts eat it, they learn the planet is run by a giant computer fed by the spray-tanned inhabitants of the planet, who never age or have sex. Kirk and company destroy the computer to save the Enterprise and to teach the inhabitants how to get freaky.
Welcome to a theme you're going to see a lot on this list: "computer running society to disastrous results." The Apple is the worst of it, because you have to wonder if The Enterprise ultimately brought more net good or net evil into the galaxy. Other computer-run societies in we see in Star Trek:TOS do legitimately kind of suck, for one reason or another. Vaal (the binary beast in question), by comparison, is benevolent (aside from a bizarre, Puritanical aversion to sex), and everyone who lives on Gamma Trianguli VI seems to have a good run of it. Okay, so Vaal has fucked with The Enterprise somehow and so must be destroyed to save the crew of 430-odd souls, but the moral question of the episode hinges around whether or not destroying Vaal is good for the planet's residents.
(Wait, I'm suddenly reminded of the TNG episode Justice....)
Maybe it was intended to be one of those stories that was bittersweet, or at least morally ambiguous, but I don't think so—the series is very fond of preaching the wonders of self-determination and independence, and whatever solution celebrates these qualities the most is invariably The Right Thing To Do (episodes where Kirk risks the crew to save a landing party of a dozen or so excluded). Sure, they don't have a hedonistic (though virgin) paradise anymore, but the people now have social progress! And sex!
There's not much of a story, or at least not one that can fill 50 minutes without padding. This episode, they up the ante by making Spock sick, killing a couple redshirts, and leaving Kirk to wonder if he's really fit for this starship captain business. Which would be an interesting conceit on its own, and actually deserves its own story. Not a perfunctory five or ten minutes in an episode that can't stand on its own legs.
The A.V. Club also took on every Star Trek: TOS episode, and noted that it would have been a cool story conceit if once in a while the Enterprise just came across some weird, fucked-up shit in the galaxy they couldn't understand or fix, and just peaced out. I agree, because that's probably want intragalactic (and intergalactic, for that matter) space travel would be like: "Well, it looks like some more weird shit that isn't exactly hostile but that we can't explain, captain." Props to Stanislaw Lem for doing exactly that. But Star Trek isn't about making that kind of weirdo, postmodern statement about the true nature of space travel, so when it doesn't give a proper history or background of any of its peoples or even monsters (or as proper as one can expect if we're operating under situations of extreme duress), it's deeply unsatisfying, Who built Vaal? How do his people seem to stay young and vital presumably into perpetuity? How does Vaal even work? Why hasn't anyone ever thought to bump uglies? If the episode had focused more on these questions as filler, instead of dead redshirts and a suddenly-insecure Kirk, it might have been passable.