History Recap / StarTrekS1E25TheDevilInTheDark

* YouNoTakeCandle: When trying to communicate its lack of hostility to Kirk and Spock, the Horta carves "No Kill I" into the rock. The potential double-meaning is acknowledged: either the Horta doesn't want them to kill her, or she doesn't want to kill, but feels she has no alternative.

* NotSoDifferent: The Horta has been killing the humans because they've been destroying her eggs, and the humans tried to kill the Horta because it had been killing their people.

* RedShirt: The poor schmuck at the beginning, as well as several more before the episode's started. One of Kirk's men also bites the dust.

* ItCanThink: The Horta steals a piece of machinery from the life-support system, revealing that it's not just a mindless beast. When Spock establishes contact with the Horta, he learns it’s highly intelligent and it burns the message “No kill I” on the ground.

* AMillionIsAStatistic: According to Spock, the death of multiple miners and even one of the ''Enterprise'' security members doesn't outweigh the cost to science of destroying a [[LastOfItsKind rare]] and valuable alien creature. However, when [[HeterosexualLifePartners Kirk]] reveals that it's within potential striking distance of him, Spock immediately tells him to kill it.

* {{Hypocrite}}: Spock attempts to defy Kirk and have the Horta brought in alive, despite the fact that it's been killing lots of miners. However, when he finds out [[TheNotLoveInterest Kirk]] is facing it, he starts urging the captain to kill it immediately. Kirk has to order him not to attack it.

* TunnelKing: The Horta, due to the acid secreted from its skin. In Kirk's own words, it's species "moves through rock the way we move through air, and it leaves tunnels. The greatest natural miners in the universe."

%%* EatDirtCheap: The Horta.

* ArbitrarySkepticism: Spock interacts with aliens that have [[RubberForeheadAliens somehow all evolved to look almost exactly like his own species]] on a daily basis, and yet it's the idea of a Silicon-based lifeform, something that is indeed scientifically plausible (if thought to be quite rare) that he finds incredulous.

* ArbitrairySkepticism: Spock interacts with aliens that have [[RubberForeheadAliens somehow all evolved to look almost exactly like his own species]] on a daily basis, and yet it's the idea of a Silicon-based lifeform, something that is indeed scientifically plausible (if thought to be quite rare) that he finds incredulous.

* RockMonster: The Horta, a silicon-based lifeform (at least [[SpecialEffectsFailure we think it's supposed to be a living rock). Calling it a "monster," however, [[SubvertedTrope turns out to be a misnomer]].

* RockMonster: The Horta, a silicon-based lifeform. Calling it a "monster," however, [[SubvertedTrope turns out to be a misnomer]].

* ItCanThink: The Horta steals a piece of machinery from the life-support system, revealing that it's not just a mindless beast. When Spock establishes contact with the Horta, he learns it’s highly intelligent and it burns the message “Not kill I” on the ground.

* ItCanThink: the Horta steals a piece of machinery from the life-support system, revealing that it's not just a mindless beast.

* MamaBear: The Horta. She’s quite upset that her eggs have been taken and she is attacking the people responsible for their disappearances. Fortunately, she is a very reasonable one and open to an acceptable compromise.

* MamaBear: The Horta. Fortunately, she is a very reasonable one and open to an acceptable compromise.

The ''Enterprise'' is called to a mining planet, where the personnel are being killed by an invisible creature. Said creature turns out to have a point of view too; she is 'the Horta' the mother of her race and the human miners have been carelessly destroying her eggs - thinking they are nothing but a curious mineral formation. These facts are established by Spock through a mind meld. The miners - to their credit - are appalled at what they have unknowingly done. And the Horta is presumably equally distressed to discover the aliens she's been killing are not deliberate child murderers. Happily both sides are willing to let bygones be bygones and Kirk is able to negotiate a peace treaty and alliance that makes the human miners - and presumably the Horta - 'Embarrassingly rich.'

* AntagonistTitle: Subverted. The "Devil in the Dark" turns out to be an intelligent being acting in defense of its brood.
** The true Devil in the Dark, turned out to be the miners who killed the baby Hortas, by damaging and destroying the mother Horta's eggs.

* EatDirtCheap: The Horta.

* MonsterIsAMommy: The Horta's motive for killing the miners - it's trying to protect its nest.

* MyGodWhatHaveIDone: Both the miners and the Horta react this way when the truth comes out - the miners are horrified to have unknowingly almost-slaughtered an intelligent species, and the Horta is dismayed that it was killing people for a crime they didn't even know they were committing. This helps both sides reach a truce.

* YouNoTakeCandle: When trying to communicate its lack of hostility to Kirk and Spock, the Horta carves, "No Kill I" into the rock. The potential double-meaning is acknowledged: either the Horta doesn't want them to kill her, or she doesn't want to kill, but feels she has no alternative.

* MyGodWhatHaveIDone: Both the miners and the Horta react this way when the truth comes out - the miners are horrified to have unknowingly slaughtered an intelligent species, and the Horta is dismayed that it was killing people for a crime they didn't even know they were committing. This helps both sides reach a truce.

!!Tropes:

* ChromosomeCasting: Not counting the Horta and a briefly-seen female extra, the episode has an all-male cast. This is the only ''Franchise/StarTrek'' production to have no female speaking parts.

* AMindIsATerribleThingToRead: Spock feels incredible mental pain when he first tries to establish a Vulcan Mind Link with the Horta. He does better on the second try, probably because the creature is more trusting.

* YouNoTakeCandle: When trying to communicate its lack of hostility to Kirk and Spock, the Horta carves, "No Kill I" into the rock.

* ChromosomeCasting: Not counting the Horta and a briefly-seen female extra, the episode has an all-male cast. There is the only ''Franchise/StarTrek'' production to have no female speaking parts.