This episode was originally produced as a second pilot, after the first pilot episode - "The Cage" - had been rejected by the NBC network as "too cerebral" for television. If you watch this episode you'll see the uniforms have not settled into their regular season designs, having sort of crew-neck collar thingies going on (though I have chosen to ignore that in this strip and represent Kirk and Spock with the same uniforms as the first two strips).

Anyway, things would have rested there and Star Trek might well never have progressed beyond a single rejected pilot, except for one influential Hollywood television producer who was a friend of Gene Roddenberry and a supporter of his concept for the show. This producer convinced NBC to consider a second pilot, which became "Where No Man Has Gone Before". NBC liked the fact that the episode was resolved with a good old-fashioned fist fight between the main hero and the villain, and the rest is history.

That Hollywood producer you need to thank? Lucille Ball.

Transcript

1
Captain's log, Stardate 1312.4. We're about to intercept an Earth ship that's been mysteriously missing for over two centuries.
Spock: Illogical.
Kirk: My move?
Spock: Playing chess at a critical time when we should be on the bridge.
2
Kirk: So what happened when the Valiant left the Galaxy?
Spock: There's no well-defined—
Dehner: The crew went nuts and started obsessing over ESP.
3
Dehner: Presumably some unknown force beyond the edge of the Galaxy twisted the minds of strong ESPers.
Kirk: Let's cross the edge!
Spock: Galaxies don't have—
Dehner: My ESP score is high, by the way.
4
Caption: But the Galaxy has a weird energy barrier!
Spock: This should not—
SFX: ZAP!
Kirk: Gary!
5
Dehner: {to Kirk} Gary Mitchell's eyes glow and he can read 100 pages a minute.
Mitchell: Hi, Jim.
Dehner: And sense things he can't see. And control the ship. But he totally doesn't have a god complex.
6
Sulu: Gary's vaguely defined power that can't be quantified is increasing... geometrically!
Spock: He has the highest ESP rating on the ship. I suggest we kill him before he kills us.
Kirk: He's my friend!
Spock: Or we could strand him on an uninhabited planet.
Kirk: Better.
7a
Mitchell: You fools! I'll squash you like insects!
SFX: Punch! {Kirk knocks Mitchell out}
7b
Spock: That should not have worked.
8
Caption: On planet Delta Vega:
Kirk: Kelso, rig up a destruct button to blow this entire facility. If Gary escapes from his cell, press it.
Kelso: Yes, captain. Nothing I love more than a suicide mission.
9
SFX: Telekinesis! {Mitchell breaks out and strangles Kelso telekinetically with a cable}
Kelso: <hack!> <choke!> I love this job!
Dehner: {to Mitchell} I knew you didn't have a god complex.
10
Kirk: How do we stop a petulant human who's been granted godlike powers?! It's not like we have to deal with this every week!
11
Kirk: I know. I'll take him on singlehanded in a fist fight.
12
Caption: And Kirk wins!
Spock: You should not have been able—
Kirk: Lesson learnt for next time we hit the edge of the Galaxy. Right, Spock?
Spock: The galaxy does not—
Caption: Cue end credits!