Original air date: January 24, 1969
There is a puzzling Class M planet that the Enterprise has come across. A planet of its young 1,000 years should not have vegetation and an atmosphere capable of sustaining life. Kirk beams down with Bones, Sulu and the not long for this universe Lieutenant D'Amato. With a "Boing!" a woman wearing enough eyeshadow to make Tammy Faye Baker cringe pops up out of nowhere and kills the ensign who's beaming the party down—with a single touch. Losira, as we later learn she's called, doesn't quite count as Girl of the Week since no one survives her touch long enough to make it with her.
Soon after, there's an earthquake on the planet and the Enterprise has another of its famous shake ups where Uhura does her best not to do a panty shot. It seems the planet and the starship have been mysteriously hurled several hundred light years away from each other. ("990.7 light years. I wish you would be more precise.") However, the image of the same strange woman appears in both places, bringing a Touch of Death with her.
While Kirk wonders if they can be saved before they starve or get touched to death, Spock is driving everyone crazy with his unrealistic expectations of a very human crew.
That Which Tropes:
- Absurdly Dedicated Worker: The automated defense computer continues defending its colony long after the entirety of the species that created her has gone extinct.
- Apocalyptic Log: The last survivor of a colony leaves a computer message for any of her people who might find it.
- Badass Normal: A redshirt saves the day by disabling the computer's defense mechanisms with his phaser.
- Baby Planet: Aversion—the fact that a Luna-sized world has Earthlike atmosphere and gravity (not to mention vegetation after only 5000 years) is one of the clues that something's amiss.
- Beauty Equals Goodness: Reconstructed.
- Losiras shown at first as a case of Face of an Angel, Mind of a Demon.Sulu: How can such people be, Captain? Such evil and she's so, so beautiful.
- They then discover they were attacked by replicas and the real Losira was a good person.Kirk: The computer was too perfect. It projected so much of Losira's personality into the replica that it felt regret, guilt, at killing. That bought us the time we needed to destroy it. She must have been a remarkable woman.
- Losiras shown at first as a case of Face of an Angel, Mind of a Demon.
- Big Damn Heroes: Kirk, McCoy, and Sulu were trapped by the multiple Losiras, until Spock and a Red Shirt arrive just in time to shoot the computer.
- Call-Back: While they're speculating about what might live on such a strange planet, Sulu mentions the rock creature from "The Devil in the Dark".
- Catastrophic Countdown: Scotty has barely seconds to pull off his job in the Jefferies Tube. Quick! Cut to a commercial!
- Continuity Nod: While wondering what killed D'Amato, Kirk briefly wonders if the rocks themselves might be alive, and Sulu recalls the silicon creatures on Janus VI. (McCoy points out that they registered as life forms, which the rocks here don't.)
- Cutlass Between the Teeth: It's a diagnostic tool rather than a cutlass, but this is how Scotty carries it into the Jefferies Tube.
- Dead Man Writing: In Losira's Apocalyptic Log about the death of her colony she says "...we who have guarded the outpost for you will be dead by the time you take possession of this planet."
- Double Vision: Going up to triple vision when the defense system generates Losiras for each of Kirk, Bones, and Sulu.
- Due to the Dead: Kirk buries D'Amato under a pile of rocks with a makeshift headstone.
- Emotions vs. Stoicism : Almost all Spocks lines in this episode.
- Exact Time to Failure: Spock can tell exactly when the core would overload.
- Flanderization: The writer really doesn't seem to get Spock — something all the stranger given that the episode's story came from D. C. Fontana, while the teleplay was written by John Meredyth Lucas, another experienced TOS writer and occasional director — having him be mystified by the human crew's use of metaphors and tendency to round off their figures, when numerous other episodes show him to be perfectly fine with these things. In this regard, he actually comes off much closer to Data. On top of that he generally behaves like a Jerkass, constantly speaking down to the human crewmembers and chewing them out over minor things, as though his usual behavior toward McCoy had been turned Up to Eleven and directed at the entire crew.
- He does use what he hears later on when he remembers Scott spoke about the "feel" of the ship being wrong. He says he doesn't necessarily understand it, but takes it seriously enough to run a computer analysis to discover what is making Scott feel this way.
- Go Through Me: After realizing that each Losira's death touch only works on the one person she's "meant for", Sulu and Bones get between Kirk and Losira to protect him.
- Gut Feeling: Scotty's feeling about something being wrong with the ship turns out to be correct.
- If I Wanted X, I Would Y: Sulu brings up The Tunguska Event. Kirk tells him if he wanted a lesson in Russian history, he'd have brought Chekov. (He'd probably add "And zat's how ze Russians inwented ze microwafe ofen!")
- Let's Split Up, Gang!: Kirk suggests this when they find themselves stranded on the planet. Once they know there is a killer loose on the planet they stick together instead.
- Logic Bomb: Kirk forces a hologram to back off by making her consider the logic of killing to protect a dead world, and why she must kill if she knows it's wrong.
- Ludicrous Precision: Spock is particularly prone to this in this episode. See Exact Time to Failure and Straw Vulcan.
- The Main Characters Do Everything: Bones is among the landing party, so Doctor MBengas back and needs to be helped by Doctor Sanchez.
- Media Watch Dog: Lee Meriwether wears a crop-top and bell bottom pants with a rectangular tab about four inches by five extending up from the waistband to conceal the forbidden sight of her navel. Will could show an entire leg, all the cleavage he wanted and occasionally side boob, but Heaven forbid we see the former Miss America's belly button!
- Mundane Utility: Kirk tries to use a phaser to dig a grave.
- The Needs of the Many: Scotty tells Spock to jettison the pod he's in to save the rest of the ship. Uncharacteristically (especially for this episode), Spock refuses even after the countdown expires, and Scotty is forced to pull another wonder out of his sleeve.
- Only One Name: Implied of Sulu; when Losira is attacking each of her victims, she calls most of them by their full names, but him she just calls Sulu.
- Opponent Switch: When Kirk realizes that each Losira projection can only kill the one she was "sent" for he has his men move to protect each other. When the computer generates three projections, one for each of them, they desperately switch things up to delay the projections for a few moments, but Kirk realizes they're in big trouble.
- Purple Is Powerful: Losira's peek-a-boo outfit is vibrant violet. She has the power to kill with a touch. In life, it was a case of Graceful Ladies Like Purple. She was a brilliant scientist who regretted that she would not live to see the habitation of the planet she helped create.
- Readings Are Off the Scale: Said several times of the readings generated by the defense system in action. One of Sulu's reports on this comes with a Reverse Polarity, followed by his statement that he's never seen anything like it before.
- Red Shirt: The body count for this ep is 3. Technically, it's one red shirt, one blue shirt and one magenta jumpsuit, but the trope still stands.
- Reverse Polarity: Spock orders Scotty to reverse the polarity of a "magnetic probe". Scotty's incredulous "Reverse polarity?!" qualifies as the Trope Namer.
- Sci-Fi Writers Have No Sense of Scale: Even before Losira causes the Enterprise to overspeed, the ship is on course to cover nearly a thousand light years in half a day. It's lucky that the good ship Voyager couldn't match this performance, or she would have been back from the Delta Quadrant in barely five uneventful weeks.
- Sole Survivor: Losira would count, if she hadn't been revealed to be a Hologram all along.
- Straw Vulcan: Spock is pretty terrible in this episode with a performance strongly comparable to his one in "The Galileo Seven".