How would this have looked in 1966? Impossibly weird or just another show set on a spaceship? It's easy to forget Star Trek did a lot of the heavy lifting for other television science fiction. When Roj Blake and his gang of freedom fighters find the Liberator in 1978 they can stand around discussing their new ship's teleport system knowing the viewer will accept it as one of those things from that show with Doctor Spock.
But what if you're a viewer in 1966? CBS has a repeat of My Three Sons and a Jerry Lewis film. ABC is showing The Tammy Grimes Show, followed by Bewitched. For some reason you don't fancy either of those so you switch to NBC. A voice-over tells you “Captain's log stardate 1513.1. Our position orbiting planet M113. On board the Enterprise Mr. Spock temporarily in command. On the planet, the ruins of an ancient and long dead civilisation. Ship's surgeon McCoy and myself are now beaming down to the planet's surface. Our mission...” And, in quick succession you see some sort of spaceship going round a planet. A weird guy in a blue top sitting in a room full of flashing lights looking at what might be a big window showing that planet again. And, 3 people appearing out of thin air in a sparkly glow. That's pretty much the first thirty seconds.
No attempt is made to ease the audience in gently. The closest thing to an explanation is Kirk's “space, the final frontier,” monologue. Even The Prisoner has an episode where Number 6 arrives in The Village and that's a series which takes pride in being wilfully obscure. Still, I'm not sure how exciting a purpose written first episode could be,” and this is the bridge... and this is Mr Spock, he's an alien from the planet Vulcan you know... and this is sick bay... and this is the transporter room....” With suspension of disbelief being such an important part of television science fiction maybe it's better to show the ship going about it's normal business. If this is all normal and routine to the crew maybe the audience will accept it even if they don't really get it at first.
So how did The Man Trap end up as the first broadcast episode? Herbert Solow (in the book Inside Star Trek) talks about meeting NBC in August to select the first episode from those that would be ready by September. The choices seem to have been The Man Trap, Charlie X, Where No Man Has Gone Before, The Naked Time, The Enemy Within, and Mudd's Women. The Man Trap and The Naked Time were the two serious candidates because they delivered on Kirk's promise of “strange new worlds” and The Man Trap was chosen. Associate Producer Robert H Justman suspected NBC viewed The Man Trap as “scarier and more exploitable” and pushed for The Naked Time but was overruled. Later he came to view The Man Trap as the better choice and I think he's right.
Look at what was available. Charlie X takes place entirely on the Enterprise and is a sweet, but slight, story about a teenage boy with psychic powers. Where No Man Has Gone Before was Star Trek's second attempt at a pilot, and is understandably a little rougher around the edges. The Naked Time is a great story but is about the crew acting strangely and so relies on the audience first getting to know the crew. It's also, and this is not a criticism, quite a funny episode which might raise false expectations about the rest of the series. The Enemy Within splits Kirk into good and evil versions; again not an idea with much traction until you know Kirk (also, do you want your first episode to be a transporter goes wrong story?). Finally, Mudd's Women is about space prostitutes.
The downside of choosing The Man Trap is it's a monster story. Not, like Arena or The Corbomite Manouver, a story which looks like a monster story to someone not paying attention. It's an honest to god monster stalking the ship killing the crew story. If you want people to take your new science fiction series seriously you probably don't want to start with one which makes it look like a monster of the week show. Especially not if your première is the day before the second series of Lost In Space starts. You can see why Robert Justman suspected NBC saw this as an exploitable episode. If you're not familiar with science fiction it probably most closely fits your expectations of the genre. Still, it's a good monster of the week story and manages to wrong-foot the audience slightly. As the last of its' species the salt vampire has some depth beyond the usual B-Movie “atomic fish beasts come to claim our Prom Queen”.
On the plus side, The Man Trap strikes a good balance between the characters. Kirk and Spock get to worry at the mystery of Nancy Crater while McCoy gets a lot of screen time from his relationship with Nancy and also when the shape shifting salt vampire doubles for him. Kirk and McCoy also get some good banter in sickbay. McCoy is explaining how crewman Darnell has had all the salt drained from his body and refers back to an earlier argument between himself and Kirk.
McCoy: Another error on my part
Kirk: (grins) I'm not counting them Bones, you in the mood for an apology?
McCoy: (smiles slightly) Forget it, I probably was mooning over [Nancy]
Kirk: (interrupts and turns suddenly businesslike) Perhaps you were
That wipes the smile off McCoy's face. It's a moment within the episode but it really sums up the complicated professional/personal relationship between the two. I also like Kirk's brusque “you bleed too much,” dismissal of Robert Crater when he pleads for clemency for the salt vampire.
Sulu, Yeoman Rand, and Uhura also get significant screen time. By the end of the episode we still haven't seen Scotty or had any real introduction to the abilities of the Enterprise; no warp drive, tractor beams, photon torpedos, or the Federation, but Spock does get to talk ominously about forcibly using truth serum on Robert Crater.
Enterprise crew deaths: 4. Crewmen Darnell, Sturgeon, Green and Barnhart.
During the first sickbay scene there's something odd going on with the medical scanner in the background. At first it's blank but when the camera moves the red object in the picture above comes into view. It looks like someone left the cover off the medical scanner and we're seeing through the set and looking at some scaffolding.
UPDATE: Over on Gallifrey Base user Mr. Flibble told me the red object is the reflection of the medicine cabinet on the other side of sickbay. He's absolutely right. What confused me was the clarity of the object, there's not even the slightest distortion of the reflection and the way it glides in as the camera pans makes it look more like an object behind the set. Originally I wondered if the scanner screen might have been pulled out as a quick solution to the screen reflecting the camera crew, but that's obviously not the case.