"The Cloud Minders" is a third season episode of the original science fiction television series, Star Trek, broadcast on February 28, 1969. It is episode #76, production #74, written by Margaret Armen, based on a story by David Gerrold and Oliver Crawford, and directed by Jud Taylor.

In this episode, Captain Kirk races against time to acquire plague-fighting minerals from a world in the midst of a civil uprising against a grievous social class disparity.

On stardate 5818.4, the Federation starship Enterprise arrives at the planet Ardana on a mission to retrieve a mineral called zenite, which is needed to halt a vegetation plague on the planet Merak II. Captain Kirk wishes to speed along the negotiations for the mineral and beams down directly to the zenite mines with First Officer Spock, despite Ardana's leader High Advisor Plasus's request to beam to the floating city of Stratos.

Once Kirk and Spock arrive at the mine, they are surrounded by angry miners and a savage brawl ensues. During the struggle, Kirk notices a strange yet beautiful woman among the rioters. Plasus quickly arrives with a security force, who easily drives the rioting miners off, then invites Kirk and Spock to go with him back to the city immediately while his people search for the zenite.

Once on the floating city, Kirk and Spock are entertained as guests until the zenite can be procured from the mines. They learn that the people of Ardana are divided between the labor-class Troglytes, who work hard in the dangerous mines, while the elite city-dwellers reap all the profits and live in luxury.

A group of Troglytes, termed Disruptors by the Stratos dwellers, are rebelling against the elites. Unknown to Kirk, the city's police have captured a Troglyte who had sneaked into the city and defaced priceless artwork. Instead of divulging the leader of the rebellious workers, the man jumps to his death from a city balcony.

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