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?


Second episode in a row in which captain Kirk's capacity of commanding is questioned. See more »


As Kirk converses with Ensign Garrovick in the ship's corridor, in their respective close-shots the curvature of the wall behind Kirk matches that of the wall behind Garrovick (who is directly facing Kirk); the corridor curvatures should be opposite for each character. See more »


Dr. McCoy: Crazy way to travel, spreading a man's molecules all over the universe.
See more »


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

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User Reviews

Ruling intelligence
9 July 2016 | by (Buffalo, New York) – See all my reviews

Another creature not in the experience of the earth led Federation is featured in this Star Trek episode. It's gaseous and without form, but has a ruling intelligence and feeds on the iron in human blood.

In fact as a young officer on the USS Farragut James T. Kirk encountered the creature and was lucky to live to tell the tale. Reminding him of that fact is a new ensign assigned to the Enterprise, the son of the late commander of the Farragut played by Stephen Brooks. It's with some mixed emotions that William Shatner deals with Brooks.

Complicating things is the fact that the Enterprise is on a critical rescue mission already when Shatner commits his vessel to fighting the creature. Something that for once Leonard Nimoy and DeForest Kelley are in agreement on and question Shatner's judgment.

Shatner shines in this Star Trek story of the difficulties of command and the problem of weighing both priorities and options. Trekkies will love this one.

1 of 1 people found this review helpful.  Was this review helpful to you?

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