Star Trek: TOS The Best Episodes

“Space, The final Frontier.  These are the voyages of the starship Enterprise.  It’s five-year mission: To explore strange new worlds. To seek out new life and new civilizations. To boldly go where no man has gone before!”


Devil in the Dark

Season 1, Episode 25

Original air date:  March 9, 1967

Stardate:  3196.1

Plot Summary:

We open on mining planet Janus 6, where the inhabitants are worried about a creature that has killed 50 people and seems impervious to phaser fire.  They await the Enterprise which is supposed to come and help them with this matter.  Schmitter is left on guard duty as the rest of the miners head back to their work, he is almost immediately killed by an unknown creature.  When the Enterprise arrives, they are briefed by Mining Chief Vanderberg about the creatures and the attacks.  The planet produces Pergium, a necessary ore for their reactors, but also contains Uranium, Platinum and almost every other element the Federation needs.  They’ve had no issues in the many years they’ve mined on the planet, but recently after breaking through to level 23 the attacks have started.  They discover that Schmitter was killed by acid burns and that there are thousands of silicon nodules in the new level, one of which the Chief has on his desk.  Spock finds this curious.

Just then another man is killed and the reactor room is broken into, a hole simply melted in the door, and a necessary piece of equipment for the circulator pump is missing.  The reactor produces the energy and breathable air for the whole colony, without the circulator the reactor will overheat and they’ll have to evacuate the planet.  Scotty beams down and rigs up a temporary fix that he is unsure will hold longer than 48 hours.  Spock speculates that the pump was purposely targeted and that perhaps this creature is a silicon-based life form. McCoy is skeptical as usual, but Kirk orders phasers modified for silicon-based life and they are hopeful the more powerful Phaser 2’s that they have will be more effective than the phaser 1’s used by the miners.

Kirk sends security teams led by Commander Giotto into the tunnels and a red shirt is almost immediately killed.  Kirk and Spock see the creature which looks like a man on all fours under a thick, ugly blanket covered in foam rubber.  They shoot at it, and while it doesn’t die it does retreat and leave a piece of it behind.  Spock examines the creature’s flesh and equates it to fibrous asbestos.  Spock speculates that the creature must secrete the acid and use it to move through rock like they move through air and furthermore the number of tunnels suggests there were once many creatures.  Since Spock’s newly adjusted tricorder can only detect one creature, he assumes this is the last of its race and laments killing it.  But kill it they must, both he and the Captain agree.  Kirk again briefs the security team with their new knowledge.  Spock mentions capturing the creature and Kirk confronts him about this when the team leaves.  Kirk tries to get Spock to help Scotty, obviously as a way to save him from having to kill the creature, but Spock doesn’t take the bait even when the Captain says it’s too risky for both he and his first officer to possibly get killed at the same time. Spock points out the odds of such a thing are 2,228.7 to one, Kirk relents.

Meanwhile Scotty’s fix fails and they have to start evacuating the planet, having only ten hours before reactor failure.  Some of the miners insist on staying behind and helping the security teams which Kirk allows.  Kirk and Spock detect the creature and assume it has gone through one of two tunnels, so they split up.  The tunnel Kirk is exploring has a cave in, we at home can see it was caused by the creature.  Spock worries about Kirk, but he says he’s fine and Spock comes to find him.  The creature tunnels through the rock and appears in front of Kirk, they have a stand-off as the creature won’t let Kirk leave but Kirk’s phaser keeps it at bay.  It is obviously wounded from the previous attack.  Spock arrives and offers to mind meld with the creature, which he does from some distance away – he senses the creatures pain.  After the mind meld, the creature uses it’s acid to write “No Kill I” in the rock.  Spock says the creature is a Horta and it is highly intelligent.  Kirk calls McCoy from the ship and Spock mind melds with the creature again.  Spock begins to shout random words; murderers, devils, cry for the children, etc.  Kirk ask McCoy to heal the creature which he tries to do after some goading.  Spock gets the creature to tell him where the missing reactor part is and Kirk heads into the “Vault of Tomorrow” to get it, where he sees more nodules, many cracked open.

When Kirk returns, he snaps Spock out of his mind meld and they agree the nodules are eggs.  The Miners overtake the red shirts who were ordered not to let them into the cavern, but Kirk tells them he will shoot the first man that tries to kill the Horta. Spock explains that the Horta are peaceful creatures, but once every 50,000 years they all die off but one, that creature lays and cares for the eggs of the next generation.  The miners broke into the hatchery and as any mother would, the Horta struck back to protect her young.  Kirk proposes that if the miners make a treaty with the Horta, they could tunnel thousands of times faster than the miners, and then the miners could extract and process the ore.  Spock mind melds again to get the Horta’s approval.  Meanwhile, McCoy, using a silicon-based cement has cured the Horta.  Spock mentions that the Horta’s logical mind was refreshing to interact with.

Back on the Enterprise, Kirk receives an update from Vanderberg about how well things are going and that the eggs are hatching.  Spock mentions that the miners feelings about the Horta being strange until you get used to them was the same thing the Horta said about humans.  McCoy asks what the Horta thought about his big ears, to which he replies that they are the feature the Horta finds the most attractive.

Known to Fans As: 

The Horta

Notable Guest Stars: 


Ken Lynch as Vanderberg.  Lynch made a career playing tough cops in movies and TV shows, even playing an Irish detective on The Honeymooners.  He’s another one of those guys that showed up on every show in the 50’s – 80’s if they ran long enough, also appearing in a few movies most prominently in North by Northwest.  Lynch died in 1990 at the age of 79 of an illness.


Barry Russo as Lt. Commander Giotto.  Russo seemed to play either a police officer or a mafioso through his many guest spots in shows and B-movies from the early 50’s through the late 1970’s. From Rin Tin Tin to Hawaii Five-O (the Jack Lord version.)  He appeared with Anthony Quinn and Robert Forster in the terrible The Don is Dead, a gangster movie rushed into production after the success of The Godfather where he played a rival Don to Quinn’s starring role.  He also appears in a couple other Trek episodes as this character.  Russo died in 2003 at the age of 78.


Continuity Issues:

Spock mind melds without touching, but mentions he can go deeper if he touches.

Kirk mentions how profitable the operation will be with the speed the Horta will grant them, once again there’s money sometimes and sometimes there isn’t.

First mentions of different types of hand phasers.

When he’s afraid for the Captain’s life Spock yells, “Jim” into the communicator – I believe that’s the first time he hasn’t called him Captain in these reviews – it was further evidence of their growing friendship.


Vulcan Nerve Pinches: None, but mind melds make the plot.


Damn it Jim: “I’m a doctor not a bricklayer.”


Kirk’s Shirt Off:  No


Aged the Best:

Silicon vs. Carbon based life, great concept that was well executed.

Kirk taking the side of a seemingly dangerous and evil creature against the miners – very enlightened.

Nimoy gets a lot to do in this episode, he’s great.


Aged the Worst:

Kirk tries to get Spock to leave by mentioning they shouldn’t both be at risk – yet that’s what happens in almost every episode.

The Horta looks terrible, comically terrible. Which is too bad because the whole concept of them is genius.

Scotty can’t fix the reactor – WTF!


Overall Grade:

A+, this was always one of my favorites, great sci-fi premise and of course a Spock-centric episode.

(Just an aside for nobody but me – my grandfather was friends with Nimoy’s parents, he grew up in Brighton, MA a few doors down from them. My grandfather, who was kind of in between the ages of them and Leonard, used to deliver newspapers to them when he was a teen and then when he became a dentist they used to go to his office in Mattapan.  I met them once when I was really young and made a fool of myself trying to get them to tell their son how much I love him.)


Tomorrow’s Episode:  City on the Edge of Forever