Star Trek (1966–1969)
28 user 7 critic

The Devil in the Dark 

The Enterprise is sent to a mining colony that is being terrorized by a mysterious monster, only to find that the situation is not that simple.


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

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TV-PG | See all certifications »


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Release Date:

9 March 1967 (USA) See more »

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Did You Know?


The reactor for the colony is the same piece of equipment in engineering that Kirk's double phasered in Star Trek: The Enemy Within (1966). See more »


Early on, Kirk asks the head miner if he placed any sentries, but he pronounces it "centuries." See more »


Capt. Kirk: Mr. Spock, give us a report on life beneath the surface.
Spock: Within range of our sensors, there is no life other than the accountable human residents of this colony beneath the surface. Eh, at least, no life as we know it.
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Alternate Versions

Special Enhanced version Digitally Remastered with new exterior shots and remade opening theme song See more »


Featured in William Shatner's Star Trek Memories (1995) See more »


Star Trek Theme
Written by Alexander Courage
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User Reviews

Silicone Based Lifeforms
6 January 2017 | by Rainey-DawnSee all my reviews

Season 1, episode 25. The Enterprise is called to Janus 6, a mining colony there are being attacked and killed by a mysterious creature. Kirk, Spock and McCoy beam down to the planet's surface with a small away crew to investigate. Upon arrival they met with Chief Engineer Vanderberg who tells them what has been going on in more detail. The search begins for this creature that can kill a person with a strong corrosive substance. The crew learn that the miners have found seemly useless silicon nodules and the creature is a silicone based lifeform. Kirk and Spock search for the creature while McCoy beams back up to the ship. Kirk and Spock find the creature hurt and Spock conducts a Vulcan mind-meld with it to learn more about it - it is called a Horta. McCoy is called back down later to help this unusual patient while the miners are ready to destroy it.

An episode that is hard to forget. I used to describe the Horta as a bubbly burnt pizza-like creature but watching it again all these years later I would say it looks more like a meatball with sauce on it. That's OK though because the Horta thinks that humans are hideous looking but the Vulcan is pleasant looking to it. lol.


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