In the opening scene a landing party which consists of Kirk, McCoy, Scotty and Uhura are unsuccessfully negotiating with a race of pacifists; they refuse to allow dilithium crystals to be mined in case they are used violently. They state that the Enterprise could take them by force but Kirk states that they won't do that. As they beam up there is an ion storm that effects the transporter; instead of finding themselves on the Enterprise they know they materialise on a ship that is almost exactly the same yet somehow totally different; this is no ship of peaceful explorers; they are part of a brutal regime where failure is punished severely and promotion is secured by assassination. In this parallel universe the crew of the Enterprise has orders to destroy the inhabitants of the planet if they refuse to allow mining; something our Kirk won't do. He and other members of the away team will have to be very careful if they are to avoid being captured before they can figure out how to get back to their own universe.
This is a classic episode that serves to introduce us to the parallel universe; a universe that will be visited more than once in later 'Star Trek' series. It is immediately apparent that the Star Fleet in the parallel universe is an organisation with fascist tendencies which immediately raises the tension. The fact that the villains have familiar faces serves to make it even more interesting it is also interesting that this Spock is just as logical as his 'good' counterpart. The cast do a fine job, especially the ones playing their evil counterparts; I particularly liked George Takei's portrayal of the thoroughly unpleasant Security Chief Sulu. Overall this is one of those episodes that no fan of the series will want to miss in fact even those who prefer the newer versions of 'Star Trek' should find this one is worth watching for its introduction to the mirror universe.
This is a classic episode that serves to introduce us to the parallel universe; a universe that will be visited more than once in later 'Star Trek' series. It is immediately apparent that the Star Fleet in the parallel universe is an organisation with fascist tendencies which immediately raises the tension. The fact that the villains have familiar faces serves to make it even more interesting it is also interesting that this Spock is just as logical as his 'good' counterpart. The cast do a fine job, especially the ones playing their evil counterparts; I particularly liked George Takei's portrayal of the thoroughly unpleasant Security Chief Sulu. Overall this is one of those episodes that no fan of the series will want to miss in fact even those who prefer the newer versions of 'Star Trek' should find this one is worth watching for its introduction to the mirror universe.