When their mission to secure a mineral trade ends in failure, a freak ion storm catches Kirk, McCoy, Uhura, and Scotty in mid-beam-up and sends them to a parallel dimension where Federation leaders are as ruthless as the Klingons, and Star Fleet promotions are attained by assassination. They find themselves on an alternate Enterprise, peopled with evil counterparts to the people they know (all attired in glittery, glam-rock uniforms), including most famously an evil, goateed Spock whom Kirk must convince to overthrow the empire. Kirk and his landing party try to fit in with this crew of villains who are threatening with annihilation the planet where the mineral trade went sour, while searching for a way back to their world and fending off assassination attempts. Mirror, Mirror achieves the best of what Star Trek is capable, which is to say space opera brought to a high pitch by melodrama. Everyone appears to be having great fun turning their characters to the dark side, especially George Takei, whose evil Sulu beams when making his assassination attempt against Captain Kirk, and Leonard Nimoy, who makes Spock's shift from the meditative logician to the ruthless goateed one seem, well, quite logical. This episode in particular fueled popular culture in such a way that in some circles it is now impossible to sport a goatee without being called "the evil Spock." The story of the evil Spock is continued in the Deep Space Nine episode Crossover. --Jim Gay
"The Deadly Years"
While on the planet Gamma Hydra IV, Kirk, Spock, McCoy, and Scotty are infected with an unknown disease that causes premature aging. The only member of the party unaffected is Chekov (Walter Koenig), who becomes McCoy's guinea pig while searching for a cure back on the Enterprise. A nifty idea with some poignant overtones, the story by David P. Harmon startles a viewer with the sight of these familiar folks rapidly graying, wrinkling, weakening, and suffering memory loss. At the same time, Harmon is careful to age each character as a unique individual. Kirk slows down more than the longer-lived Spock, while McCoy remains mentally keen, if physically brittle. As for poor Scotty, well...
The dramatic subtext in "The Deadly Years" concerns the perennial conflict over when and how to decide that someone has become too old to execute crucial responsibilities. In that sense, this episode feels constantly relevant and uniquely entertaining: let's just say some of these actors play "old" a little better than others. (Director Joseph Pevney has reported that there was a lot of conflict over who was stealing old-guy moves from whom.) With all this going on, one might not notice that guest star Charles Drake is a truly familiar face, having been cast in The Maltese Falcon and Now, Voyager. --Tom Keogh