When miners on Janus VI are being murdered by a creature that can move through solid rock, chief engineer Vanderberg contacts the Enterprise and asks for assistance in hunting it down. What they discover is that this so-called creature is actually an intelligent creature known as the Horta and that it has only killed to protect its young, which are encased in silicone shells that the miners mistook for worthless rocks.
The U.S.S. Enterprise arrives to investigate reports of an unknown monster deep in the mining tunnels of Janus VI. The being is apparently destroying machinery and killing the miners, and has the ability to burrow through solid rock. Janus VI is a source for the rare mineral, pergium.
Soon after the landing party arrives on the planet's surface, a reactor pump is stolen and the colony is in jeopardy from fluctuating life support functions. However, this convinces Spock that they are dealing, not with a mindless monster, but with an intelligent lifeform.
Kirk and Spock, along with members of the ship's security team, enter the mines to find the creature. They discover a large, rock-like creature that burrows easily through the stone walls, as a mole might burrow through dirt. Wounded in a phaser blast, the bulky creature manages to escape through the stone wall.
They continue pursuit and eventually Kirk is trapped by the creature. When it doesn't attack, Spock attempts a Vulcan mind meld with the entity and discovers that it is, in fact, an intelligent being. A native of the planet, the creature is normally peaceful, and called a Horta. It doesn't mind sharing the planet with the miners, but when the men broke into the Horta's hatchery and unknowingly destroyed many of her eggs, it attacked to protect its remaining unborn children.
With Spock acting as interpreter, the miners explain that they thought the eggs were some king of silicon nodules and that no hostility had been meant.
McCoy treats the silicon-based creature, with a trowel and patch material, and heals it. An alliance is formed between the Horta and the miners; the young, newly hatched Hortas will mine the pergium at a far faster rate than the humans could and the miners will be extremely rich. Kirk retrieves the missing reactor and the landing party leaves the inhabitants of Janus VI living in peaceful co-existence.
By MITDGreenb on 01 Jul 2007 04:50:55 Unfortunately, I have to rat ethis one a little low. There are many production errors (like the guy's foot coming out from under his Horta suit) and a preachy theme about "can't we all get along." At the same time, I personally have always LIKED this episode for some reason. It's my favorite "I'm a doctor not a ..." line and the whole Spock "Kill it, don't kill it" angst. Not the gem of some episodes but by far not the worst either.