And so we continue.
17 - The Squire of Gothos

The Enterprise runs into a seeminly omnipotent being who wants to have some of the crew as playthings. Kirk objects, and so the episode involves the crew trying to find the source of the being's power and shutting it down. Having just watched the second season 'Apollo' episode, the two are very similar (right down to the fact that the beings are recreating eras in Earth history). The being fancies himself as a Napoleonic era general and appears besotted with that time, so there's juxtaposition between Kirk, the enlightened contemporary man, and the violent man of the past. There's a really interesting moment when the crew realise the food looks great, but doesn't taste good, and I like that it's this revelation that leads to them to conclude that the being has weaknesses and that therefore there is a way out. And Kirk, always the thinking man, is able to goad the being into hunting him to buy some more time - cue action scene. In the end, the episode has shades of Charlie X, complete with a deus ex machina resolution to the crew's predicament. So the climax seems to fizzle out.
18 - Arena AKA Gorn Attack

The Enterprise chases a raider ship responsible for the destruction of a colony, but then a race of powerful beings trap Kirk and his raider counterpart on a planet where they must personally face each other in combat. Except that the raider is a Gorn, with must greater physical strength and durability. Kirk thus needs to find a way to even the odds. It's wonderful to at last see this one, the episode that seems to have had such an influence on popular culture and the rest of Trek, to see where the Galaxy Quest joke really comes from ("Look around you, can you form some sort of rudimentary lathe?"). This is Kirk at his best in my view, striving to use his brains to solve the problem, and getting exhausted and beat up a lot like a vulnerable human rather than a superhero.
The Enterprise tends to run into a lot of these superbeings on their journey, and it's not always the most interesting premise for an episode, but I feel that this has the most satisfying ending; the race thinks we might be worth talking to in a few thousand years (when we've overcome our baser instincts). I'm a fan of Stargate SG-1, and one of the best episodes in that long running series was called The Fifth Race, in which the Asgardian aliens also believe humans will ultimately be worthy. I suppose I'm an optimist
19 - Tomorrow is Yesterday

Oh my god! This is where the whole flying into the sun to go back in time thing comes from! This is the kind of unexpected joy that I've had watching the series. The Enterprise is accidentally sent back into the late 60s (what a coincidence eh?) and as they fly through Earth's upper atmosphere they're discovered by an American pilot. They attempt to use a tractor beam (I forget why) and are forced to beam the pilot aboard when his jet breaks apart under the stress. The pilot thus becomes exposed to the future and can't be returned to the surface in case he changes the course of history. And whilst they wrestle with that dilemma, they have to work out how to return to their own time. I loved this episode, including a scene where Kirk is interrogated by some security guards and is almost obnoxiously cool.
Spock makes a mistake in this one which really surprised me. He comments that the pilot has made no contributions to history, but completely neglects to consider any of his descendents! That's a schoolboy error. But then it's Original Series Trek, which means that it's merely the set-up for more great interplay between Kirk, McCoy and Spock.
20 - Court Martial

I love, love, love this episode. Kirk is faced with a court martial after evidence is found on the Enterprise computer that he wrongfully jettisoned a pod containing one of his crewmembers (killing him) during a storm. Former classmates don't believe him and spurn him and the victim's daughter screams at him, Kirk is in trouble but is adamant that what he did was the right thing to do - even though it clearly pains him that it resulted in the death of someone he once considered a friend. He gets a craggy old lawyer to defend him and thus the stage is set for an engaging trial, which is superior to Spock's trial in Menagerie in every way. We also, finally it seems, get an actual female character, a smart and independent lawyer who prosecutes the case against Kirk. She used to be former flame of his years ago, but doesn't fall into his arms like every other hormone-controlled woman on the show, and is conflicted because she's going against a friend and not because of love; she nevertheless still does her job, and does it excellently. She's still played by a stunning actress (there isn't a single remotely unattractive female cast in the entire season), but she's not dressed up for the amusement of a powerful being and, to my recollection, isn't photographed in that awfully corny soft focus manner. There's a scene near the end which is masterful, and is probably the smartest thing I've seen on TV in a long while. Granted, it may have been born from budget constraints but if anyone did it now, a superb, suspenseful scene would have been replaced by a dull 'deck by deck search'.
The more I see of Shatner's Kirk, the less impressed I am of Abram's/Pine's version. It's not a pale shadow, it's a completely different and totally inferior character.