Star Trek (1966–1969)
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Operation -- Annihilate! 

The Enterprise crew attempts to stop a plague of amoeba-like creatures from possessing human hosts and spreading throughout the galaxy.



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Episode complete credited cast:
Joan Swift ...
Maurishka ...
Yeoman Zahra
Peter Kirk (as Craig Hundley)
Fred Carson ...
First Denevan
Jerry Catron ...
Second Denevan


The Enterprise traces a virus-like outbreak that seems to be traveling in a direct line across a planetary system. The next planet is home to Kirk's brother Sam, his sister-in-law and their young son. The Enterprise arrives too late however for Sam. They find flying jellyfish-like creatures that attach themselves to humans. They take over the victims nervous system forcing them to bend to their will. Spock finds a weapon to use against the creatures but it leaves him hopelessly blind. Written by garykmcd

Plot Summary | Plot Synopsis


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Release Date:

13 April 1967 (USA)  »

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Technical Specs


Sound Mix:


Aspect Ratio:

1.33 : 1
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Did You Know?


Some non canonical Star Trek novels have given the explanation that Sam Kirk's two other sons (spoken of in What Are Little Girls Made Of) were away from Deneva during the events of the episode. It has also been suggested that Sam Kirk having three sons was part of the misinformation Kirk planted in his robot double in What Are Little Girls Made Of. See more »


When Spock stuns the creature to take as a specimen, it lands face down, but close-ups show it face up. See more »


[Spock, infected, beams down to the planet to collect a specimen]
Dr. McCoy: Jim, that man is sick - and don't give me any damnable logic about him being the only man for the job.
Capt. Kirk: I don't have to, Bones. We both know he is.
See more »


References Star Trek: What Are Little Girls Made Of? (1966) See more »

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User Reviews

Pretty Pedestrian Effort
28 April 2014 | by (United States) – See all my reviews

We sadly learn of the death of Kirk's brother, wife, and son. They have been victimized by an influx of rubbery creatures that latch on to their victims and do in their central nervous systems. Kirk vows to find a solution to this problem. Spock is investigating the things but fails to check out his surroundings. As he walks under an archway, one of the creatures, previously stuck to a wall, flies through the air and settles on his back. He is immediately overcome with excruciating pain. The crew is able to stun one of the creatures and it is brought to Dr. McCoy for analysis. McCoy tries every kind of approach he can think of from poisons to heat to shooting and stabbing but nothing works. It is when they realize that one of the victims said as he approached the sun that he was free that they try one last thing: light. The remainder of the episode involves their efforts to test their light theory, being stopped short because to do this, you need a host that has been assaulted by this creature. It is the quest for such a host and more tests that make the conclusion quite interesting.

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