Star Trek (1966–1969)
28 user 6 critic

The Devil in the Dark 

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


Joseph Pevney


Gene L. Coon, Gene Roddenberry (created by)

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Episode complete credited cast:
William Shatner ... Capt. Kirk
Leonard Nimoy ... Mr. Spock
DeForest Kelley ... Dr. McCoy
Ken Lynch ... Vanderberg
James Doohan ... Scott
Brad Weston Brad Weston ... Appel
Biff Elliot ... Schmitter
George Allen George Allen ... Engineer #1 (as George E. Allen)
Jon Cavett Jon Cavett ... Guard
Barry Russo ... 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

Plot Summary | Plot Synopsis


TV-PG | See all certifications »


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English | Latin

Release Date:

9 March 1967 (USA) See more »

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Did You Know?


This takes place in 2267. 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 William Shatner's Star Trek Memories (1995) See more »


Star Trek Theme
Written by Alexander Courage
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User Reviews

Fine plot, bad monster even for a TV show...
7 June 2009 | by rixrexSee all my reviews

I'd rate this as a good Star Trek thanks to the typically literate plot, and of course great cast as always, but the execution of the monster is really sub-par even for TV shows from this time. It was great watching as a kid when first televised, but then we thought every episode of Lost in Space was great too.

In fact the monster here is just too reminiscent of that other show, and really too much like the infamous creature in The Creeping Terror. I really think someone like Stan Winston would have done a much better job even with the same basic creature design. And those silicon eggs!? At least they could have had a textured surface, not perfectly smooth and shiny like a kid's play-ball or balloon. Well, even Star Trek has blunders. Other than this, a fine episode.

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