Kirk and Spock transport to the planet Organia, a pastoral realm of very low technology, which has the misfortune of being strategically important to the Klingons, who plan to use Organia as a forward base when they war on the Federation. Despite Kirk's best efforts, he cannot seem to impress upon the Organians that they are in dire peril and should ally with the Federation. Then the Klingons arrive, and being imposing martial law, and taking and executing hostages. Kirk works behind the scenes to interfere, but when the Organians betray him to the Klingons, he starts to wonder if they are worth protecting.
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Complete story — includes the ending
Peace negotiations have collapsed between the Federation and the warlike Klingon Empire. The Enterprise is ordered to protect Organia, a peaceful planet located near the Klingon border. Kirk and Spock beam to the surface to warn the Organians about the Klingons, but a Klingon fleet soon arrives, forcing the Enterprise to abandon the duo on the planet. The natives protect Kirk and Spock, even as Kor, the new Klingon governor, orders mass executions of the Organian people. As both Federation and Klingon fleets converge above the planet, Kirk and Spock execute a daring raid on the Klingon headquarters in an effort to destabilize their control over the planet.
Sources and content license
Source and revision history · Adapted from Wikipedia contributors, Star Trek: The Original Series season 1. HTML formatting and reference markers removed. · Content license