In order to get Star Trek on the air, Gene Roddenberry says that he had to sell it as a Western, a "Wagon Train to the stars", and that certainly does show up in some episodes ("Mudd's Women", "The Conscience of the King"). However, I would venture to say that it's really more of a horror series than anything else -- the horror hiding inside a sci-fi shell, which in itself hid inside a Western shell. The world of the original Star Trek is one filled with supernatural beings, many of whom can bear the image of your best friend, and many of whom are completely beyond human comprehension. These beings, almost to a man, are out to kill you.
The setting is in space, but the show rarely tells genuinely science fictional stories, proceeding from a "what-if" question about our future. Star Trek takes place on the outskirts of civilized space, so we don't get much of a picture of what this future society looks like. Instead, we have the cold darkness of space, a space you apparently can't go two feet in without running into some Lovecraftian god beyond your comprehension. Two of the three episodes directly before "Arena" ("Shore Leave" and "The Squire of Gothos") dealt with beings who were or at least seemed all-powerful, although those two took a more humorous tack.
"Arena" is an action episode though, and not a humour episode, or one of the more overt horror or science-fictional episodes. From the start we're immersed into fighting, a shootout on a ruined Federation outpost, which leads to a warp-speed chase, until the Enterprise and its mysterious enemy run into the home of a race of god-like beings, who chide them for being more violently and promptly force Kirk and the enemy captain to fight mano y mano. The end of the episode makes a plea for mercy and understanding, but structurally this a story told entirely through violence, and very aestheticized violence at that.
We start in on the fighting almost immediately, beaming down to an alien planet that is being, to use the scientific terminology, having the shit bombed out of it. Full-scale war is at this point unknown to the peaceful, near-utopian world of Star Trek -- but the Enterprise exists on the fringes of that utopia, the unexplored frontier that fuels the Western genre Roddenberry claimed to channel. So we have full-scale warfare -- but it's a rather odd depiction of that warfare. Six Enterprise members beam down into some kind of central pavilion, where they are then continuously bombed from afar. The previously unseen and unnamed security officers die, of course (these are the infamous "redshirts", although their shirt colour is actually much more varied than I had been lead to beleive). The regulars then run around the open area dodging remarkably inaccurate bombs. Kirk even evades some by his patented Shatnerian acrobatics, and then takes them out with a powerful grenade that looks like a blue eggshell.
From a realist perspective, this scene is ridiculous. The idea that the main characters (and only them) can survive industrial warfare by tucking and rolling is silly, and turns a mass battle into something that can be solved by individual heroism. But Star Trek isn't trying to be realistic SF (and no, that's not a contradiction). Instead it's more of a mythic, fantastical storyline, where Kirk is a larger-than-life hero that's both in charge of the ship and does all of the exciting adventuring. It's also interesting to note the futuristic weaponry, which looks cute but causes a massive explosion. Like most of the technology in Star Trek, it's not really important to the plot, and exists without much comment from our characters. Obviously weapons technology has developed considerably in 200 years, but it's still a shock when we see the massive explosion the grenade generates. But it's just a shock, and it passes.
It's worth also noting the landscape in the screenshot above. Star Trek is a world of bright primary colours -- the three uniforms we see Starfleet officers in are red, blue and yellow -- and landscapes that have an almost radioactive glow. This can be seen in the bright yellowish-brown backdrop, with a clear blue sky, where the initial battle takes place. We also get a version of that same background later in the episode, on the "arena" planet, although this one has enough mountainous scrub brush that it looks almost Leone-esque.
Obviously the technical limitations of the era were a large part of this look. But I think it also reinforces the almost mythic qualities of the story. Even in space, there's very little darkness in Star Trek. It's not a coincidence that both of this episode's battles take place in sets that look plopped right out of a Western.
The chase scene that follows is a more genuine attempt to adapt the rhythm of another genre to science fiction, and it doesn't quite work -- we're stuck in the stationary Enterprise no matter how fast everyone says they're going. When Kirk takes the ship up to Warp 8, we get a rough idea that it's dangerous from the rest of the crew's reaction, but the lack of worldbuilding stops this from being much more than technobabble -- the show never tells us exactly what's significant about Warp 8. The scene is like something out of a radio play, where we hear the action being tersely described instead of seeing it, and that's not good for a series that relies on visual novelty as much as Star Trek does.
The aliens this week are actually a great example of that visual spectacle. As much as science fiction claims to be a literature of ideas, it makes more profit as a vehicle for outlandish thrills, from the trashy covers of pulp magazines to the massive success of Star Wars. The Gorn is an attempt at such an appeal, and a departure from the usual human-with-weird-ears-and-forehead approach to aliens. Instead it's the guy-in-a-suit approach reminiscent of kaiju movies.
This is the carnival-esque novelty appeal (something similar to Gunning's "cinema of attractions") that you find often in early TV. In other words, "our show might not have the best writing, but it's the only one with a giant lizard man". "Arena" even acknowledges this by having the other characters watch this fight on the big screen from the bridge of the Starship, shot exactly as we see it -- even in the show's world this fight is a spectacle. The Metron, the all-powerful beings du jour, represent the other side of Star Trek, the wannabe-cerebral side side prone to morality plays. They even look angelic (and extremely effeminate), evoking all sorts of age-old theological questions about why God allows war. (It's apparently to punish us for being violent, at least according to Star Trek.)
This side of the story doesn't really bear too much scrutiny. The Metron are an alien species that views humans as barbaric and violent, a fairly familiar sci-fi trope, but their solution to intruders is to make them fight to the death and wipe out the loser, which doesn't exactly seem like something a peaceful society would do. Also, while Kirk eventually chooses mercy, he does so only after blasting the Gorn with a cannon that could have killed it. It's easy to be peaceful when you have the other guy on the end of your phaser.
This is really quite typical of the Golden Age sci-fi that Star Trek takes its cues from, which often tried to convey rather staid allegorical Lessons (by the time Trek aired there was already a backlash against this in the New Wave movement of SF). There's an uncomfortable enjambment of didactic, Asimovian science fiction and the raw dumb joy of the pulps here. And on a further level, there are all the other genres thrown in the stew of Star Trek, at least a few of which I've tried to get to above -- horror, epic, Western. This is probably why Star Trek was such a cult phenomenon -- the mass audience didn't know how to respond to a show so far outside of the genre templates (even fans of more pure SF shows like The Twilight Zone), but for those who enjoyed the weird alchemy, it was the best thing on television.
While it's easy to pick at the flaws in "Arena" from a distance of forty-plus years, it doesn't change how striking an episode it is. We don't get a chance to breathe -- like I said about Bob Newhart last week, the whole episode is of one cloth, without a B-plot in sight. Contemporary shows have a comfortable rhythm that usually requires us not to spend too much time in one place or on one subject, making it all the more striking when there is an extended scene (e. g. the long confrontation scene in Mad Men's "The Gypsy and the Hobo"). We can see the alternative in this episode, which is essentially a 50-minute action sequence. It's unrelenting, it sometimes drags, and it's sometimes uncomfortable, but you nevertheless can't take your eyes from it.
This is what created a cult following that's still talked about (usually jokingly) today. Star Trek is a show that's easy to mock but impossible to forget. In this episode Kirk defeats the more physically powerful Gorn by using his chemistry knowledge to construct a cannon. Science triumphs over brute force -- and strangely enough, the square-jawed conventional leading man Captain Kirk becomes a symbol for the triumphant nerd, the weak but smart triumphing over the big brute. History was being made, where no man had gone before but many would go after.
Next week: "I love you. I love being heterosexual with you. But if for some reason you're not feeling it, just let me know, so I can find another woman to be heterosexual with. Because I have needs."
This would make Firefly a lot less of an original fusion than it's often described as, although Whedon uses the "space Western" concept a lot more literally.
I'm tempted to say that this unity of plot is characteristic of older TV shows, but I really haven't watched enough to speak definitively.