19 user 7 critic

Errand of Mercy 

With a war with Klingons raging, Kirk and Spock attempt to resist an occupation of a planet with incomprehensibly placid natives.


John Newland


Gene L. Coon, Gene Roddenberry (created by)




Episode complete credited cast:
William Shatner ... Capt. Kirk
Leonard Nimoy ... Mr. Spock
John Abbott ... Ayelborne
John Colicos ... Kor
George Takei ... Sulu
Nichelle Nichols ... Uhura
Peter Brocco ... Claymare
Victor Lundin ... Lieutenant
David Hillary Hughes David Hillary Hughes ... Trefayne
Walt Davis Walt Davis ... Klingon Soldier
George Sawaya George Sawaya ... Second Soldier


War! The Klingons and the Federation are poised on the brink, and then war is declared. Kirk and Spock visit the planet Organia. Organia, inhabited by simple pastoral folk, lies on a tactical corridor likely to be important in the coming conflict. Whichever side controls the planet has a significant advantage. But the Organians are a perplexing people, apparently unconcerned by the threat of the Klingon occupation or even the deaths of others in their community. Finally, Kirk and the Klingon commander Kor learn why, and the reason will change Federation/Klingon relations for decades to come. Written by CommanderBalok

Plot Summary | Plot Synopsis


TV-PG | See all certifications »


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Release Date:

23 March 1967 (USA) See more »

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Did You Know?


For some reason, Lt. Sulu is left in command of the Enterprise instead of 3rd in command, Lt. Commander Scott ("Scotty"). There is no in-universe explanation provided. See more »


When first describing the mind scanner, Kor tells what effect it would have on a Vulcan (Spock) and on a human (Baroner, who is really Kirk). At this point, Kor does not know that any humans are present. He thinks "Baroner" is an Organian. See more »


Kor: You have done well to get this far through my guards.
Mr. Spock: I believe you'll find that several of them are no longer in perfect operating condition.
See more »

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 »


Theme From Star Trek
Written by Alexander Courage
See more »

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User Reviews

An excellent script and parallels with Nazi Germany
3 January 2011 | by taragem72See all my reviews

"Errand of Mercy" is one of this reviewer's favorite. Indeed, guest star John Colicos, who plays the series' first Klingon commander, took the part because of the excellent script. The episode involves the Enterprise being sent to peaceful Organia to prevent the Klingons from using it as a strategic location in its expansion and enslaving its apparently primitive and non-violent inhabitants. However, instead of accepting Kirk's offer of help to prevent a Klingon take-over the Organians don't appear to be the least bit interested, to the consternation of Kick and Spock. Meanwhile, in space the Federation and the Klingon Empire prepare for all out war, paralleling Nazi Germany's expansion and the US being drawn into WW II. In true TOS fashion, the plot twists take you on a merry roller-coaster ride, each more fantastic than the last. Colicos' role as the Klingon Commander is superbly acted, portraying the ruthlessness and violent nature of the Klingons. Mr. Colicos was supposed to appear in that role in future episodes, but was unfortunately unable to due to other acting obligations. A tight script and surprise ending make "Errand of Mercy" one the TOS best.

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