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. However, when the Enterprise arrives at Vulcan, complications at the ceremony may endanger Captain Kirk as well. (Season Premiere)

This episode was written by Theodore Sturgeon, he also wrote the Season 1 episode "Shore Leave."

As the first ever Star Trek episode to feature any Vulcan characters other than Spock, this episode introduced several important elements of Vulcan culture.

Besides establishing the concept of pon farr, it also marked the first use of the Vulcan salute (by T'Pau) and of the words, "Live long and prosper" (by Spock). It also established the trend among almost all female Vulcans to have a name beginning with a "T" and apostrophe (in this case T'Pau and T'Pring).

In the original script, there were a few more Vulcan words. Spock described Kirk and McCoy as his lak noy, the equivalent of best man. When T'Pring makes her challenge, the wedding party begins to discuss what's going on, all in Vulcan, until T'Pau shuts them up.

Theodore "Ted" Sturgeon, born Edward Hamilton Waldo in 1918, was a prolific science fiction author, who made his mark in the Star Trek universe, crafting the backstory for Spock and the Vulcans in TOS: "Amok Time", an episode that garnered him a Hugo Award nomination.

In later life, he lived in Oregon, where he died in 1985.

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