You know how often at the end of a ''Star Trek'' ep they'll show a CreditsMontage, often ending with a [[NightmareFace creepy, blue alien face]]? Well, this is the ep that still came from! And if you watch it all the way through, [[NightmareRetardant that face won't seem so scary anymore.]] Ironically enough, facing your fears is the [[AnAesop Aesop]] of this episode.
An ordinary day on the ''Enterprise''. Kirk is taking a required physical, so Spock has the chair. Suddenly, they run into what looks like the [[AppleMacintosh Apple Spinning Beach Ball of Doom]] that they just can't seem to escape. When evasive maneuvers fail, Spock calls for a red alert. Navigator Bailey, who's struggling to deal with all this, suddenly becomes a little trigger happy until Kirk reminds him who's in charge. Kirk tells Bailey to plot a spiral course at increasing speeds to get away from this NegativeSpaceWedgie. When it starts emitting radiation, Kirk orders to open fire, destroying the object.
Just when everything looks peachy keen, the ''Enterprise'' is caught in the tractor beam of what looks like a cross between the [[DisneyThemeParks EPCOT's Spaceship Earth]] and a popcorn ball. The message identifies the sphere as the ''Fesarius'', the flagship of the First Federation, and the speaker as her commanding officer, Balok. Balok announces that the crew of the ''Enterprise'' has exactly ten minutes to bend over and kiss their collective asses good-bye. If only Kirk can come up with a cunning plan....
!!Tropes for this episode include:
* AssPull: [[invoked]] An example of the "Character Made It Up On The Spot" It worked so well, he pulls it out again for some Romulans in "The Deadly Years".
* AttackReflector: Kirk threatens to do this (as a bluff) with a device embedded in the ''Enterprise'' that would reflect any attack back at an aggressor.
* BigLittleMan: The ''Enterprise'' encounters an alien vessel, and is able to get a video feed revealing the bridge, which shows the alien captain, Balok, to be a scowling monster that looks to be about 7 feet tall. However, later they manage to get on board, revealing they had actually been watching an elaborate puppet show, and the real Balok is no larger than a child.
* BrandishmentBluff: This is Kirk's cunning plan: "This is the Captain of the ''Enterprise''. Our respect for other life forms requires that we give you this... warning. One critical item of information that has never been incorporated into the memory banks of any Earth ship. Since the early years of space exploration, Earth vessels have had incorporated into them a substance known as... corbomite. It is a material and a device which prevents attack on us. If any destructive energy touches our vessel, a reverse reaction of equal strength is created, destroying... the attacker. It may interest you to know that since the initial use of corbomite more than two of our centuries ago, no attacking vessel has survived the attempt. Death has... little meaning to us. If it has none to you then attack us now. We grow annoyed at your foolishness."
* ChessMotifs: Spock compares their situation to a game of chess. "Not chess, Spock." says Kirk. "Poker!"
** Bailey tells Spock "Raising my voice back there [[BlatantLies doesn't mean I was scared or couldn't do my job.]] It means I happen to have a human thing called an adrenalin gland." Spock responds "It does sound most inconvenient, however. Have you considered having it removed?" Sulu tells him he should know better than to try to out-snark Spock.
** Kirk gets a snark at Bailey's expense after Bailey "votes" to open fire when he tells him "I'll keep that in mind, Mr. Bailey...when this becomes a democracy."
* EarlyInstallmentWeirdness: This was actually the first episode filmed after the pilot, and some of the details were still in flux.
** Uhura wears a gold uniform.
** The ''Enterprise'' is referred to as an Earth ship rather than a Federation ship.
** Spock yells rather emotionally.
** A random crewman wears a life jacket. On a spaceship.
* EldritchStarship: Balok's starship ''Fesarius'' was a gigantic starship the size of a small moon, composed of a sphere made up of smaller spheres of various sizes and colors. At least one part of this ship could break off as a smaller command vessel. It's possible that the ship was composed entirely of smaller vessels to the aforementioned one, clustered together and sharing power.
* FaceDeathWithDignity: Possibly the reason why Bailey asks permission to resume his post with one minute left on the clock. He takes up most of that minute just walking to his seat!
* FreakOut: Bailey has one when he realizes [[Literature/TheHitchhikersGuideToTheGalaxy1 "So this is it; we're all going to die."]]
* HelloNurse: Yeoman Rand. Kirk has a hard time ignoring her charms.
* HeroicBSOD: Bailey has a disturbing tendency to [[Literature/WatershipDown tharn out]] in times of stress. He might think about a transport ship. There's a lot less pressure there. Staying on the ''Fesarius'' works too.
* IComeInPeace: Kirk says this to Balok.
* IgnoredVitalNewsReports: [=McCoy=] sees the alert light, but prefers to complete Kirk's physical. Presumably [=McCoy=] also turned off the sound, since Kirk heard neither the alert, nor Spock's calling him to the Bridge.
* IResembleThatRemark: Kirk berates [=McCoy=] for not telling him about an alert. After the former leaves the latter alone, [=McCoy=] says "If I jumped every time a light came on around here, I'd end up talking to myself."
** Inverted - Kirk claims that Bones always says "a little suffering is good for the soul". Bones flatly denies it, and he never finds occasion to say it or anything similar in any subsequent episode or movie. (This is given a ContinuityNod in [[Film/StarTrek the reboot film]], where Bones ''does'' say it - of course, that's a different Bones.)
** Kirk also claims that Bones has said "Man is ultimately superior to any mechanical device". Bones denies this, too, but he's probably lying (Kirk's bemused reaction suggests this), and he does make similar statements in many subsequent episodes, such as "The Ultimate Computer".
* JekyllAndHyde: Balok name checks the famous duo that's really an uno. However, it seems more of a disguise than a true split personality. And the method Balok used had much more in common with ''Film/TheWizardOfOz''.
* MadLibThrillerTitle: The Corbomite Maneuver
* MagicCountdown: A fairly subtle example. During the ten-minute countdown to the Enterprise's destruction, the minutes that pass on screen are nearer a minute and a half long.
* TheManBehindTheCurtain: Balck has the appearance of a human child. When he communicates with other ships via the view screen, he uses an intimidating puppet. Notably, Balok's method was more like [[Film/TheWizardOfOz another noted man behind the curtain]] than it was Jekyll and Hyde.
* MundaneUtility: Rand uses a phaser to heat up the coffee the Captain absolutely must have.
* MustHaveCaffeine: Who cares if the ship's 'bout to blow up? Kirk needs that coffee, dammit!
* NotSoDifferent: During their conversation at the end of the episode, Balok points out several things he and Kirk have in common, such as the fact that each is proud of his ship.
* OneSteveLimit: averted with the alien First Federation only because the creators had not yet established The United Federation of Planets.
* OOCIsSeriousBusiness: There's a great character moment when Kirk berates Spock for his apparent acceptance of defeat: Spock almost says, "I'm sorry", before catching himself and reporting that he sees no logical alternative.
* PickyEater: Kirk doesn't really want salad, but Bones says he's putting on weight.
* PrepareToDie: The ''Enterprise'' is confronted by a powerful alien vessel that announces its intention to destroy our heroes, and goes on to say — "we assume you have a deity... or deities," and politely offers to give the Enterprise crew time to make "whatever preparations" they deem necessary. An unusually explicit example of this trope, where the opponent says "prepare to die" and clearly ''actually means it''. And they're all the scarier for that.
* RaceAgainstTheClock: They only have 10 (Earth) minutes to get out of this. Sulu is watching the clock for them when Balok isn't reminding them. Scotty eventually gets annoyed by Sulu's counting down, saying he has "an unhealthy obsession with timepieces".
** At one point the editors forgot to dub in Balok's reminder - leading to Sulu's cryptic, "I knew he would" line (which actually gets cut in syndication).
* ReadingsAreOffTheScale: Spock says this of Balok's mothership when they're attempting to measure its size.
* SciFiWritersHave/NoSenseOfMass: The ''Enterprise'' encounters a mysterious cube, which Sulu says is 107 metres on each side and masses just under 11,000 metric tonnes. Scotty says it must be solid metal, leaving him wondering how it could be powered and how it moves around. But the quoted measurements give a density of about 9 kilograms per cubic metre, significantly less than Styrofoam - implying the cube is almost certainly hollow (they may have been aiming for 9 tonnes per cubic metre, which is between the densities of iron and lead, and dropped a factor of a thousand somewhere).
* SciFiWritersHaveNoSenseOfScale: The Enterprise is 289m long, yet it dwarfs the 107m cube. The Fesarius is a mile in diameter (1609m) according to Spock, yet it dwarfs the Enterprise from 5km away, appearing a hundred times bigger.
* SecondEpisodeIntroduction: This is the first non-pilot episode of ''Star Trek''. Introduced are Uhura, Yeoman Rand, and Dr. Leonard "Bones" [=McCoy=] (as a SecondEpisodeSubstitute for Dr. Mark Piper); it is not, however, the second episode aired, as the pilot episode "Where No Man Has Gone Before" was held back until later in the first season.
* SecretTestOfCharacter: After the Enterprise breaks free of Balok's TractorBeam, Balok sends out a distress signal indicating that the struggle overloaded his ship's systems and he's now stranded far from any help his own people might send. Kirk decides to beam over and offer the Enterprise's assistance, whereupon it turns out that Balok's ship is fine and he just wanted to learn what Kirk would do. (He also says that the entire encounter has been a test of character, to make sure that the Enterprise's protestations of peaceful intent are genuine. It's not clear, however, what would have happened if the destruction countdown had run down without Kirk thinking up the corbomite maneuver.)
* SeeTheWhitesOfTheirEyes: The cube initially stops over 1500 metres from the Enterprise, although on-screen they appear nose to nose with each other. Later the cube gets closer than 51 metres before phasers destroy it. (That's closer than half the cube's size.)
* ShirtlessScene: Kirk removes his shirt for a physical exam. Guess they decided it was more dignified than a butt-baring hospital gown.
* SmartPeoplePlayChess: In light of this episode, maybe the trope should be "Book Smart People Play Chess" and a new trope be called "Street Smart People Play Poker".
* StayWithTheAliens: After the alien reveals it was all a SecretTestOfCharacter, he asks for a human to teach him about humans. Kirk sends the crew member that was pushing for the alien's death earlier. (Maybe he just wanted to get rid of him?)
* TalkingToThemself: Bones is quite alone when he says "Humph...if I jumped every time a light flashed around here, I'd end up talking to myself."
* ToWinWithoutFighting: Kirk is able to bluff his way out of a fight by convincing his potential enemy that to engage his ship would result in [[TakingYouWithMe their immediate destruction in turn.]]
* TractorBeam: Balok's ship is equipped with one which he imprisons the Enterprise with.
* TwoOfYourEarthMinutes: "We therefore grant you ten Earth time periods known as "minutes" to make preparations."
* VideoPhone: In many episodes, but at its greatest effect here.
* VocalDissonance: Balok is played by a very young Clint Howard, but with Vic Perrin's (some sources say Walker Edminton's) voice. Ted Cassidy voiced Balok's puppet.