Star Trek (1966–1969)
26 user 5 critic
Trapped in an alien laboratory, Kirk, Spock and McCoy meet an empath and are involved in a series of experiments.


John Erman


Gene Roddenberry (created by), Joyce Muskat

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Episode complete credited cast:
William Shatner ... Capt. Kirk
Leonard Nimoy ... Mr. Spock
DeForest Kelley ... Dr. McCoy
Kathryn Hays Kathryn Hays ... Gem
Alan Bergmann Alan Bergmann ... Lal
James Doohan ... Scott
George Takei ... Sulu
Davis Roberts ... Dr. Ozaba
Jason Wingreen ... Dr. Linke
Willard Sage ... Thann


Kirk, Spock and McCoy suddenly find themselves in an underground laboratory where they meet an attractive young woman who is not only mute but also an empath who can absorb someone else's pain. When their captors make themselves known, they refuse to explain why the three men have been taken prisoner or why they and the young woman, whom McCoy has named Gem, are there. Inexplicably, they set about torturing them for no apparent reason. Fortunately, Gem's empathic powers allow her to take away their pain, but only at great sacrifice to herself. When their captors tell Kirk that he must choose which of his men to die, their selflessness comes to the fore, leaving Dr. McCoy volunteering himself. They all soon learn that the object of the experiment is Gem herself. Written by garykmcd

Plot Summary | Add Synopsis


TV-PG | See all certifications »






Release Date:

6 December 1968 (USA) See more »

Company Credits

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Technical Specs


Sound Mix:




Aspect Ratio:

1.33 : 1
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Did You Know?


This episode contains another one of McCoy's famous, "I'm a doctor, not a..." quotes. In this episode it is "coal miner". See more »


When Kirk is being tortured it is easy to spot the suspension ropes holding him from the hips, which also account for his unnatural position. See more »


Captain James T. Kirk: If my death is to have any meaning, at least tell me what I'm dying for.
Thann: If you live, you will have your answer.
See more »

Alternate Versions

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


Referenced in Star Trek: Discovery: The Vulcan Hello (2017) See more »

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User Reviews

sacrificially worth it,in spite of budget issues
29 July 2007 | by uneecycleSee all my reviews

I realize that they had budgetary issues that might be evident in it,but I must agree that the theme of self-sacrifice was indeed a valid one,regardless of any script opinions.The way the empath showed compassion,projected the pain of others on herself,and even healed.Hmmm..theologically mirrors a similar character that we all know who Im referring to!(and it's a Good thing!)True,with all the dark corners of this "underground lab..cost-cutting could easily be inferred, many other 60's shows did the same thing?Irwin Allen's sci-fi series were notorious for's interesting what can be redeemed in spite of working with limited raw materials.

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