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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.


Herschel Daugherty


Steven W. Carabatsos, Gene Roddenberry (created by)




Episode complete credited cast:
William Shatner ... Capt. Kirk / Sam Kirk
Leonard Nimoy ... Mr. Spock
DeForest Kelley ... Dr. McCoy
James Doohan ... Scott
Joan Swift ... Aurelan Kirk
Maurishka Maurishka ... Yeoman Ellen Zahra
Majel Barrett ... Nurse Christine Chapel
George Takei ... Sulu
Nichelle Nichols ... Uhura
Craig Huxley ... Peter Kirk (as Craig Hundley)
Fred Carson 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


TV-PG | See all certifications »

Did You Know?


This is one of only three original series episodes in which the word "damn" is used, with McCoy cursing the "damnable logic" behind the experiments designed to destroy the blastoneurons. The only other uses of the word "damn" occur in Star Trek: The Original Series: Journey to Babel (1967), wherein Kirk admits he can't "damn" Spock for his loyalty by taking command of the Enterprise at the cost of Sarek's life, and in Star Trek: The Original Series: Court Martial (1967) where Kirk makes a log entry stating that the evidence against him is "damning." During the 1960s, "damn" and "hell" were usually considered unacceptable on television (although hell might be allowed for naming a theological locale, as in several The Twilight Zone (1959) occasions). This remained the case until All in the Family (1971) came along in 1971. See more »


Before the Enterprise leaves orbit, there is a close-up of the helm and navigation consoles; a crewman in a red tunic can be seen at the helm. Previous and subsequent shots show Sulu at the helm in his standard gold tunic. See more »


Spock: I am a Vulcan, doctor. Pain is a thing of the mind. The mind can be controlled.
Capt. Kirk: You're only half Vulcan. What about the human half?
Spock: It is proving to be an inconvenience, but it is managable.
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Alternate Versions

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


References The Brain Eaters (1958) See more »


Music credited to Alexander Courage, although it strongly resembles the main title music for 'Hollow Triumph (1948)' by Sol Kaplan
Sung by Loulie Jean Norman
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User Reviews

Strange Flat Creatures, Spock Blinded
7 January 2017 | by Rainey-DawnSee all my reviews

Season 1, episode 29. The Enterprise is tracking a strange straight line pattern where all of the inhabitants of the planets in line are going crazy and dying - some are killing themselves. The next planet in line is Deneva, a Federation Outpost where Kirk's brother Sam is stationed. Kirk, Spock & McCoy beam down to the planet to investigate and to visit Sam and his family. What they find are strange flat flying creatures attacking people and everyone on the planet are either going crazy, dying or already dead. When they get to Sam's place they find Sam is dead, Sam's wife starting to go mad then suddenly dies and Sam's son in a comatose state and dying. Spock is attacked by one of the creatures. The 3 beam back aboard the ship with Kirk's comatose nephew. Kirk, Spock and McCoy race to find the answers and cures, in the process Spock is blinded.

I actually found this episode quite entertaining. The dialogue between Kirk, Spock and McCoy is really good. It shows just how great of a team the three of them are: different ideas, opinions but working together they create good theories and solutions.


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Greek | English

Release Date:

13 April 1967 (USA) See more »

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