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?


The ship which Kirk served on for his first deep space mission is disclosed to be the USS Farragut, and was named after David Glasgow Farragut, a flag officer of the United States Navy during the American Civil War. He was the first rear admiral, vice admiral, and admiral in the United States Navy and is credited for uttering the phrase, "Damn the torpedoes, full speed ahead!," disregarding all danger while charging into enemy waters off the Alabama Coast. See more »


In the first scene, Spock phasers off a sample of rock, which has been clearly pre-cut to fall off on command. See more »


Nurse Chapel: Your self-pity's a terrible first course. Why don't you try the soup instead?
Ensign Garrovick: I told you, Christine, I'm not hungry.
Nurse Chapel: Dr. McCoy thought you might say something like that. This is his officially logged prescription for you. It has one word on it: eat. Now if you don't follow his orders, Dr. McCoy could and possibly would have you hauled down to Sickbay and fed intravenously.
See more »


Referenced in Star Trek Continues: The White Iris (2015) See more »

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User Reviews

15 June 2009 | by (The San Francisco Bay Area) – See all my reviews

Sayeth Captain James T. Kirk to his good friend a chief medical officer Doctor Leonard McCoy.

Or, Trek does Herman Melville. I remember seeing "Moby Dick" on TV quite a few times, and even the mid late 1970s iteration with Richard Harris and Bo Derek with Shamu in the antagonistic role of "Orca". So it is that I never really fully absorbed this episode until a few years back when I bought the first DVD publication of the classic Star Trek series.

It's a story about pining for a second chance, and, as the title states, obsessing about that second chance when it's presented. But the story also makes clear that the decisions we make, we make out of the best judgment we have at the time. As my former coworker told me one time "Could've, would've, should've, who knows?", and that's what the author of this screenplay is telling the audience. The author even goes a step further and seals the deal with a definite answer for both characters and audience by stating what would have happened.

This story hit home for me when I first popped it in my DVD player. I grew up with Trek as a kid, and reflecting on my own past experiences, I can truly appreciate this story and its parable for what it is, and embrace the full value of the message. Sometimes we go through life with an astonishing amount of regrets, berating our past performances for not achieving the goals we strove for. But, as long as we gave our full best effort at the time, it is reasonable to expect any better result? In the US we call it Monday-Morning quarterbacking; i.e. looking at a game of American "Football", and critiquing the mistakes of who made what decisions, and the impacts thereof. We learn from our mistakes, but how much dissection is healthy? Or, to put it in simpler language, do we really need to beat ourselves up for something over which we had no control?

Production Values; the monster is what it is--a cloud. Animated at some times, dry ice sunk in a pale of water at other times. It's not the most abhorrent or scary of creatures to look at, but it does give one pause when we consider its capabilities, and its true nature. In other words, again another fantastic sci-fi story carries forward some slight of hand special effects. We know what we're looking at, but the attributes of the monster as explained in the dialog and scene action and description, are what carry the story forward.

Again, this is the genius of shows like Star Trek. The material future may be the polar opposite of dystopic, but it's the forces inside us meeting the challenges without that create our own spiritual and psychological desolation. This episode, like all good TV, lets us vicariously travel that path as Kirk and crew address a menace to 23rd Century space lanes; a sociopathic (or perhaps just callous and uncaring) sentient that has its own priorities: Survival.

And here again we're given a pretty harsh story on top of that. In a galaxy and universe like Star Trek, where the usual baddies come in the form of Klingons or misunderstood (sometimes super powerful) alien races, will there always be room for a heart to heart negotiated settlement? And what will the ramifications of that be like? This too is worth pondering.

Gripping, mysterious, somewhat belabored in the subplot department, but a good watch all the same.


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