On the planet Janus VI, Chief Engineer Vandenberg supervises the mining team at the Federation pergium colony. Something has killed 50 of their men and Vandenberg and his men relieve a sentry while waiting for the Enterprise
to arrive. The new guard goes on duty by himself, but a mysterious alien creature strikes from the shadows and reduces him to a burnt corpse.
If you hear anything or see anything, call in. Somebody can arrive in three minutes.
A lot can happen in three minutes.
arrives and Kirk, Spock, and McCoy beam down to meet with Vandenberg and his assistant Appel. The deaths began three months ago after the miners hit upon a new vein. After that, something started destroying machinery and then killing men. The last man died three days ago in an upper level as the creature has moved steadily upward. Appel describes the creature as a huge shaggy beast immune to phaser fire. Spock is intrigued by a spherical silicon nodule, and Vandenberg explains they discovered it in a cavern but it has no value. McCoy examines one of the corpses and discovers that they were killed by corrosive acid. The Federation needs the pergium from the colony and Kirk is the one sent to make sure it's produced.
Mr. Vanderberg, I'll need a complete subsurface chart of all the drifts, galleries, tunnels.
You'll get it.
The creature kills a guard at the colony's reactor chamber and takes the main circulating pump. The reactor starts to go critical and Scotty determines they only have 48 hours before it explodes, even after he rigs a temporary replacement. Spock concludes the creature is intelligent and deliberately stole the part, and they wonder why the creature is attacking now. Spock believes the creature is connected to the silicon nodules and believes that the attacker is a rare silicon-based lifeform with a thick enough hide to resist Level I phasers. They order the security guards to use Level II phasers while Spock continues to examine the nodule.
Look, we didn't call you here so you could collect rocks.
security teams begin to patrol the tunnels and Spock suggests they start at Level 23, where the nodules were found. Spock and Kirk join the search and Spock detects a silicon lifeform as well as smooth tunnels that the miners aren't responsible for. The creature kills an Enterprise
security guard and Kirk and Spock are the first on the scene and find his charred corpse. They hear a rumbling noise and the creature emerges from a newly formed tunnel. They open fire with the Level II phasers and drive it back, removing a piece of its hide. They believe the creature is more dangerous then ever now that it is wounded.
He never even had a chance to fire, Captain.
Spock manages to track the creature by its silicon lifeform readings but suspects that it is the last of its race because there are more tunnels then one creature could account for. Kirk orders the security teams to fire to kill, despite Spock's concerns they may be killing a creature that is the last of its kind. Kirk tries to assign him to Scotty's repair team but Spock insists that he be in the field and the odds of both he and Kirk being killed is unlikely. Kirk tries to evacuate the miners but Vandenberg, Appel, and some of the others insist on remaining to hunt down the creature, with clubs if need be. Kirk and Spock go out with the security teams but have to split up to follow the creature's tunnels. Kirk discovers more of the silicon nodules and Spock advises him not to damage them. The creature brings down the tunnels behind them, cutting them off, and then advances on Kirk.
I'll take a lifeform reading.
It's not necessary, Mr. Spock. I know exactly where the creature is.
Kirk threatens it with its phaser and it stops, but refuses to either leave or advance. It blocks the captain's pat leading onward. Spock comes up behind it, concerned for Kirk, but the captain suggests they hold off since the creature isn't threatening him at the moment. The creature turns arond and reveals the wound it suffered earlier from their phaser fire, and they notice more of the nodules nearby. Spock attempts a mind-meld but falls back, overwhelmed by the creature's pain. It then shuffles over to a rock and, having learned English from the meld, burns the words "No Kill I" into its surface. They're not sure if it's a promise, or a plea for mercy. Spock has learned about the creature from the meld and says it is a highly intelligent being which calls itself a Horta.
What is that, a plea for us not to kill it, or a promise that it won't kill us?
Spock needs to meld further with Horta to learn what it did with the reactor pump and why it started murdering the miners. The creature lets him do so and while they commune, Spock calls in McCoy and has the security guards hold back the miners. Spock speaks of the thousands dying, the end of eternity, and the "Chamber of Ages." Kirk has McCoy tend to the creatures wound while Spock directs Kirk to the pump within the Chamber of Ages. Kirk finds the Chamber filled with more of the silicon nodules... and the pump. He comes back and Spock emerges from the meld to reveal that the nodules are the Horta's eggs and the miners inadvertently destroyed thousands of them.
Pity! The thousands... devils! Eternity ends... The Chamber of the Ages... The altar of tomorrow! Murderers! Stop them! Kill! Strike back! Monsters!
The miners fight their way past the security guards and prepare to kill the Horta, but Kirk tells them to back down and explains what's happened. Spock has learned that once every 50,000 years all but one Horta dies, and it acts as the caretaker for the eggs of the next gneeration. The creature was peaceful until the miners threatened its children, and still returned the circulating pump. McCoy heals the creature using quick-hardening cement from the ship's stores, while Spock proposes that the miners make an arrangement with the Horta to find rare minerals that lay beyond conventional digging equipment. The miner agrees and as the Enterprise
leaves, Vandenberg lets them know that the eggs have hatched and they're already locating new ores. Spock admits he finds the Horta's mental processes intriguing, but Kirk notes that Spock may be biased because the Horta likes his pointed ears.
I'm beginning to think I can cure a rainy day.