The Enterprise discovers a planet exactly like Earth, but the only inhabitants are children who contract a fatal disease upon entering puberty.



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Episode complete credited cast:
Keith Taylor ...
Jahn's Friend
Ed McCready ...
Boy Creature
Kellie Flanagan ...
Blonde Girl
Stephen McEveety ...
Redheaded Boy (as Steven McEveety)
David L. Ross ...
Lt. Galloway (as David Ross)
Jim Goodwin ...
John Megna ...
Little Boy


The Enterprise receives an old style SOS signal and finds on arrival a planet that is virtually identical to Earth. Kirk, Spock, McCoy and Yeoman Rand beam down to the planet only to find that it is inhabited solely by children. Kirk befriends one of the older children, Miri, but they soon learn that experiments to prolong life killed all of the adults and that the children will also die when they reach puberty. They also learn that the children are in fact, very old. Soon, the landing party contracts the virus and has seven days to find a cure. Written by garykmcd

Plot Summary | Plot Synopsis

Plot Keywords:

puberty | virus | cure | boy | child | See All (45) »


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Release Date:

27 October 1966 (USA)  »

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Aspect Ratio:

1.33 : 1
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Did You Know?


This was the first episode produced by Gene L. Coon, and Gene Roddenberry (previously the line producer) serving as Executive Producer. See more »


At the end, Captain Kirk tells Mr. Spock, "Full ahead, warp factor one" which Spock repeats back to him, however, Mr. Spock is sitting at the science station (his normal station) and not at the helm, which is where the ship's movements are controlled. While Spock is not at the helm, this exchange is reflective of Naval command structure where the Captain tells the First Officer what he wants done and the First Officer orders the Crew. This was not the normal for Star Trek The Original Series as it progressed, but it reappeared in Star Trek: The Next Generation with Number One giving the orders. See more »


Capt. Kirk: This is the vaccine?
Dr. McCoy: That's what the computers will tell us.
Mr. Spock: Without them, it could be a beaker full of death.
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Referenced in South Park: The Wacky Molestation Adventure (2000) See more »


Theme From Star Trek
Written by Alexander Courage
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User Reviews

"I never get involved with older women"
9 April 2009 | by (Italy) – See all my reviews

Miri is one of the strongest and most gripping episodes of the original Star Trek, providing a pretty shocking spin on the age-old post-apocalyptic Earth scenario (except for the fact that none of this takes place on Earth, obviously).

The location is a planet which is an exact replica of Earth: same continents, atmosphere, buildings (albeit a bit old-fashioned) and people. Actually, there's a problem with the people: the planet is inhabited exclusively by children. No Stephen King-like twists (à la Children of the Corn), though: as Miri (Kim Darby) explains to Kirk, all the adults were wiped out several years ago by a virus which doesn't affect children. Dr. McCoy quickly comes to the conclusion that the virus works only on individuals who have already reached puberty, and with every crew member of the Enterprise - apart from Spock, as usual - starting to show symptoms, their exploratory mission becomes a race against the clock to find an antidote before someone gets killed, be it by the virus or Miri's more uncooperative "peers".

A lot of science-fiction thrives on the idea of what our planet would be like without specific groups of people. In this case, however, the story serves as a much more potent reflection on a seemingly trivial theme like puberty: a simple plot gimmick like a virus becomes a powerful metaphor, using the opportunities given by the sci-fi context to explore previously uncharted territory and delivering a compelling portrait of young people yearning to be part of the grown-up world even though they aren't quite ready for that yet (this is most obvious in the case of the titular character and her feelings for Kirk). The fact that it's a tense and scary story helps a lot, too.

14 of 18 people found this review helpful.  Was this review helpful to you?

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