Capt. Kirk obsessively hunts for a mysterious cloud creature he encountered in his youth.



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Episode complete credited cast:
Stephen Brooks ...
Jerry Ayres ...


Captain Kirk is haunted by a creature from his past when conducting a mining survey on a planet. He first encountered it as a lieutenant aboard the U.S.S. Farragut and blames himself for freezing in a moment of crisis, causing the death of many crewmen. The creature is a cloud-like, gaseous being that lives on the red blood cells found in humans. Obsessed by his desire for revenge and to erase the memory of 11 years ago, he pursues the creature relentlessly, putting in jeopardy an assignment to collect essential medical supplies. Written by garykmcd

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Release Date:

15 December 1967 (USA)  »

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Aspect Ratio:

1.33 : 1
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Did You Know?


This takes place in 2268. See more »


At the hearing, Ensign Garrovick describes the creature as being "several cubic meters" in size, but his distance as "about twenty feet away," mixing two different systems of measurement. It's unlikely that people in the Trek Universe would have any use for the antiquated, inefficient system of feet and miles. See more »


Spock: Do you know what it is, Captain?
Capt. Kirk: [referring to the lethal gaseous entity] Something that can't possibly exist... but it does.
[looks on to dead crewmen sprawled on the ground]
See more »


Featured in Bring Back... Star Trek (2009) See more »

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User Reviews

I Haven't the Foggiest
29 April 2014 | by (United States) – See all my reviews

Kirk is carting around baggage from eleven years ago, when he failed to act as a cloud that smelled sweet, like honey, appeared and several were killed. The crew is extracting some incredible ore when Kirk recognizes that smell. Three red shirts are sent to investigate. Two are killed by the cloud and one is badly injured. The Enterprise is supposed to dock with the Yorktown to bring important medical supplies. All Kirk can think of is the power of that cloud which has reintroduced his biggest failure. The cloud sucks the red corpuscles out of the bodies of its victims. A young ensign, son of an old friend of Kirk's is enlisted, and fails, just as Kirk did, to kill the foggy entity. The thing travels through space and the issue becomes what can be done to stop it. Simple phaser fire doesn't work. Kirk now becomes psychologist and pursuer as he allies himself with the young man. It works pretty well.

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