As the Enterprise approaches planet Omega IV, they find another starship, the U.S.S. Exeter, in orbit. Kirk, Spock and McCoy beam aboard to find the ship abandoned but strewn with uniforms and crystals. The last log entry from the ship's surgeon tells them they have been infected with a deadly virus brought aboard from a returning landing party. Kirk's party beams down to the planet's surface and finds there is one Exeter survivor: Captain Ron Tracey. He has apparently ignored the Prime Directive and has taken sides in a local dispute supporting the Kohms against their arch-rivals, the Yangs. As McCoy tries to find a cure for the virus, Spock and Kirk try to make sense of the situation. They eventually realize there is an odd parallel with Earth's own history. Written by
Did You Know?
NBC announced that Star Trek would be renewed for a third season during the closing credits of this episode, on 1 March 1968. In the announcement, they also wrote "Please do not send any more letters", responding to the vast amount of mail received during the protests organized by Roddenberry and Bjo Trimble. See more
Spock indicates he found Captain Tracey's spare phaser power packs surrounded by several hundred Yang bodies. The implication is that the Yangs were killed by Tracey's phaser. However, phasers set to kill completely disintegrate the person (as demonstrated when he kills the red-shirt). See more
Captain James T. Kirk
Among my people, we carry many such words as this from many lands, many worlds. Many are equally good and are as well respected, but wherever we have gone, no words have said this thing of importance in quite this way. Look at these three words written larger than the rest, with a special pride never written before, or since, tall words proudly saying, "We the People". That which you call Ee'd Plebnista, was not written for the chiefs of kings, or the warriors or the rich or the powerful, but ...