"Amok Time" is the second-season premiere episode of Star Trek: The Original Series. The episode first aired on September 15,1967 on the NBC Network. Written by Theodore Sturgeon and Directed by Joseph Pevney.
Baffled by Spock's behavior, Kirk is listening in the corridor to McCoy go on about how Spock has stopped eating. The two continue their conversation as they approach Spock's quarters, in time to see the first officer push Nurse Christine Chapel out of his quarters and physically hurl the Vulcan plomeek soup bowl she prepared for him after her. Stunned by this extremely unusual behavior for their fellow Vulcan first officer, Kirk and McCoy immediately question Spock after this outburst. Spock, in an emotional tone, demands that Captain Kirk grant him a leave of absence on his home planet Vulcan.
Kirk orders Spock to sickbay, where McCoy examines him and finds the half-human/half Vulcan Spock is suffering from extreme stresses resembling those produced by high levels of adrenaline in Humans. Kirk gives Chekov orders to plot a course for the Enterprise to head to planet Vulcan.
Later in his quarters, Spock explains to Kirk that Vulcans must also periodically return home to mate. Vulcans do not typically discuss this mating cycle even among themselves, instead masking the emotional drives of it in archaic ritual, as it is shameful for such a logical race to be overcome by urges so powerful as to strip them of their intellect and veneer of civilization. Spock has reached his time, the pon farr. Suffering through his first infliction of pon farr, the Vulcan biological mating urge, Spock must return to Vulcan to marry his betrothed or he will die.
Upon the arrival of Enterprise at Vulcan, A beautiful Vulcan woman appears on the main bridge viewscreen, and she exchanges formal greetings with Spock. When asked by Lieutenant Uhura who she is, Spock states that she is "T'Pring, my wife," much to the shock of Kirk, McCoy, and others on the bridge.
As Spock's friends, Kirk and McCoy are invited to witness the marriage ritual – the koon-ut-kal-if-fee. T'Pring chooses Kirk as her champion, over the strenuous objections of the Vulcan Stonn, another member of the wedding party, who is present and clearly wants to be with T'Pring. T'Pring chooses a 1-on-1 battle for her hand in Vulcan Marriage, choosing Captain Kirk versus Spock.
Kirk agrees to the challenge. It is only then Kirk is informed that this is to be a fight to the death and is given a Lirpa weapon, consisting of a metal staff with a fan-shaped blade on one end and a club on the other.
After Spock is in a deep trance like state he seemingly kills Captain Kirk, but McCoy actually knocked him out with a hypospray that had a delayed reaction.
Complimenting T'Pring's logic, Spock relinquishes T'Pring to Stonn, but advises him that "having is not so pleasing a thing as wanting. It is not logical, but it is often true."
The lesson of the story
As human's we often times find that understanding another culture, or in this case an off-world culture has traditions that come down from the times of their beginning, without change at the heart and soul of their ways. Very different as these traditional ways may be, as friends, this acceptance and understanding will contain several important elements of knowing the friends culture and much of what they are truly made of. The opposite end of the friendship is a two way street though, after Spock thought he had killed his friend Kirk at the hands of his unusual cultural practices, much of his own interests and ways caused death. In this moment the priestess officiating at Spock's formal wedding named T'Pau tells him "Live long and prosper, Spock." Spock stunned at the death of his friend Kirk, responds "I shall do neither. I have killed my captain and my friend."
 Thanks to the story and nostalgia generated by "Amok Time", it was listed as the 5th best episode in the 1991 Star Trek Viewers Choice Marathon hosted by Shatner and Nimoy.
- "Amok Time" at Memory Alpha Star Trek wiki