"Amok Time" is the second-season premiere episode of the original science fiction television series, Star Trek. It is episode #30, production #34, first broadcast on September 15, 1967, in the series' new time slot of 8:30 pm on Friday night, and repeated April 26, 1968. This was the first episode to feature regular cast member Walter Koenig, as the ship's navigator, Ensign Pavel Chekov, and also the first one to list DeForest Kelley as Dr. McCoy in the opening credits. It was written by science fiction author Theodore Sturgeon, scored by Gerald Fried, and directed by Joseph Pevney.

The episode features First Officer Spock returning to his homeworld for a brutal Vulcan mating ritual. It is the only episode of the series to depict scenes on the planet Vulcan.

Spock, the first officer of the Federation starship USS Enterprise starts exhibiting irrational behavior and requests that he be taken to his home planet Vulcan. Captain James T. Kirk and Chief Medical Officer Dr. McCoy, having witnessed one of their friend's outbursts, agree and divert the ship to Vulcan. En route, Kirk receives orders from Starfleet to travel to Altair VI to represent the Federation at the inauguration ceremony for the planet's new president. Though Kirk instructs the crew to set course to Altair VI, Spock secretly changes course back to Vulcan. Kirk confronts Spock, who claims having no memory of ordering the course change.

Kirk orders Spock to Sick Bay, where McCoy finds his blood chemistry is extremely active with a high hormone count, a condition that will kill him in seven to eight days if not treated. Spock is forced to explain that he is undergoing pon farr, a condition male Vulcans experience periodically throughout their adult life, and that he must mate or die. Kirk contacts Starfleet to request a diversion to Vulcan but is denied. Kirk disobeys orders and sets course to Vulcan, believing that saving the life of his friend is more important than his career.

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