Star Trek (1966–1969)
28 user 5 critic

The Devil in the Dark 

The Enterprise is sent to a mining colony that is being terrorized by a mysterious monster.



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Episode complete credited cast:
... Capt. Kirk
... Mr. Spock
... Dr. McCoy
... Vanderberg
... Scott
Brad Weston ... Appel
... Schmitter
George Allen ... Engineer #1 (as George E. Allen)
Jon Cavett ... Guard
... Giotto


The Enterprise travels to the planet Janus 6 to assist the mining colony there. Kirk, Spock and McCoy beam down to the planet where Chief Engineer Vanderberg tells of a creature loose in the mine tunnels killing some of his men. The monster seems to appear out nowhere then disappears just as quickly. Finding that the creature, known as a Horta, lives in a newly opened part of the underground mining complex, Spock uses the Vulcan mind meld to determine why it is killing the miners. Written by garykmcd

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TV-PG | See all certifications »


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Release Date:

9 March 1967 (USA)  »

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Did You Know?


The clubs used by some of the Janus VI colonists during their hunt for the Horta appear to be of the same design used by Kirk during his fight with Spock in the transporter room in Star Trek: This Side of Paradise (1967). See more »


When deciding which of two tunnels to investigate, Kirk tells Spock to take the one on the left, and he'll take the one on the right. But he gestures with his phaser to the exact opposite tunnels. See more »


Mr. Spock: The Horta is badly wounded. It may die.
Dr. McCoy: It won't die. By golly, Jim, I'm beginning to think I can cure a rainy day.
Captain James T. Kirk: Can you help it?
Dr. McCoy: Helped it? I cured it.
Captain James T. Kirk: How?
Dr. McCoy: Well, I had the ship beam down 100 pounds of that thermal concrete. You know, the kind we use to build emergency shelters out of 'em. It's mostly silicone. So I just troweled it into the wound, and it'll act like a bandage until it heals. Take a look. It's as good as new.
Captain James T. Kirk: Well, Mr. Spock, I'm gonna have to ask you to get in touch with ...
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Featured in Star Trek: Science vs. Fiction: Das Beamen (2006) See more »


Star Trek Theme
Written by Alexander Courage
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User Reviews

Still a favorite after all these years
13 May 2007 | by See all my reviews

Kirk and the crew are visiting a federation mining colony on a remote planet rich in mineral resources. The Devil in the Dark is the Horta, a very unusual silicon based life-form which tunnels through solid rock. The Horta has been killing miners and, it is decided, must be destroyed. But how?

It is hard to continue this review without writing a spoiler, so instead I simply concentrate on the technical aspects of the episode and touch on its themes. The special effects are OK, but many of the scenes with the Horta look a little absurd. The acting is fairly average for TOS. Some of the miners are a little awkward. Nimoy has the most difficult role of all in Devil in the Dark, and he pulls it off well.

Why is this still a favorite of mine?

Devil in the Dark is really an anthropological and ecological morality play disguised as an adventure. More than many episodes of this great TV series, it brings home the importance of maintaining an open mind and at least some degree of empathy toward others. Plus, it involves one of the most interesting, if not probable, plot twists in the original series.


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