|Season 2, Episode 1|
|Air date||September 15, 1967|
|Written by||Theodore Sturgeon|
|Directed by||Joseph Pevney|
|Operation - Annihilate!||Who Mourns for Adonais?|
|Star Trek episodes|
Spock must return to Vulcan to mate with his wife but is accidentally drawn into mortal combat with Captain Kirk.
Doctor McCoy stops Captain Kirk in one of the hallways of the U.S.S. Enterprise and informs him that First Officer Spock has been behaving strangely, almost nervously, and hasn't eaten in three days. The captain is initially unconcerned, however when the two witness Spock's violent outburst when Nurse Chapel brings him soup, it becomes obvious that something is very wrong.
Spock requests a leave of absence to his home planet of Vulcan. When Captain Kirk demands an explanation for why Spock insists on taking shore leave, Spock avoids the question, asking Kirk to accept only that he needs rest. Captain Kirk obliges him by ordering a change of course to Vulcan.
When The Enterprise receives a priority signal ordering them to proceed to Altair VI a week earlier, they no longer have time to divert to Vulcan, and a direct course to Altair VI is once again laid in. Later, Kirk has second thoughts and asks Mr. Chekov how long their arrival would be delayed if they diverted to Altair VI at maximum speed. Chekov informs him that they are already en route to Vulcan per Spock's orders. Kirk confronts Spock, who says he has no memory of changing the order. Spock begs Kirk to have him locked up, but Kirk instead orders him to report to sickbay for examination. Upon examining Spock, Dr. McCoy concludes that he is in fact suffering from some unknown medical condition and informs Kirk that Spock knows what it is but won't tell him, and that he is probably correct in his assertion that he will die in eight days if he doesn't get help on Vulcan.
Kirk once again confronts Spock and demands to know what's wrong, after an emotional appeal fails, he tries logic, stating that if he is at risk of losing one of the best first officers in the fleet he wants to know why. Spock finds it very difficult to discuss, saying that "it is a deeply personal thing" and that "there are some things that transcend even the discipline of the service". When Kirk states that it will be kept confidential, Spock states that his condition is called pon farr, a which "must return to that one stream where they were born, to spawn…or die trying".
Kirk contacts Starfleet Admiral Komack at to request permission to divert to Vulcan, however the admiral denies the request. Kirk disobeys orders, reasoning there are already two other starships attending the inauguration and they would be delayed by a day at most.
Upon The Enterprise's arrival to Vulcan, Spock requests that Captain Kirk and Dr. McCoy accompany him to the surface. He tells them that Vulcan marriages are arranged in childhood, and they fulfill this commitment when they become adults. Spock's betrothed is a woman named T'Pring.
T'Pau, a highly revered Vulcan, who was the only person to ever turn down a seat in the Federation Council, officiates over the ceremony. T'Pring arrives accompanied by Stonn, a pure-blooded Vulcan, who is clearly her lover. She invokes the right of koon-ut-kal-if-fee, a battle between Spock and her chosen champion, but instead of Stonn she picks Kirk to represent her. Spock objects because Kirk "does not understand" their customs. T'Pau allows Kirk to decide, telling him another champion will be selected if he wishes to decline. Kirk accepts the challenge intending to let Spock win - until he discovers that it is to be a fight to the death.
The two fight with Lirpas, traditional weighted Vulcan blades. McCoy tries to intervene telling T'Pau that Kirk is seriously disadvantaged as a non-Vulcan due to the planet's heat, thinner atmosphere and higher gravity. T'Pau refuses to intercede, but allows McCoy to inject Kirk with a triox compound to counteract the Vulcan environment.
When the combat resumes, Spock garrotes Kirk with another traditional Vulcan weapon, the Ahn'woon, and when he falls limp Doctor McCoy takes his pulse and pronounces Kirk dead. Then he beams back to the Enterprise with Kirk's body.
After the battle, Spock renounces his claim to T'Pring, but questions her choice of Kirk as her champion. In a display of logic that impresses Spock, T'Pring explains that she did not wish to be the consort of a famous Vulcan such as himself, and she shared a mutual attraction with Stonn. Since she could only legally divorce Spock through the koon-ut-kal-if-fee, and allowing Stonn to take the challenge as her champion would risk losing him, she instead chose Kirk, knowing that regardless of the outcome she and Stonn would be together — as Kirk would not want her and Spock would probably release her. Even if Spock held her to her vows, he would return to Starfleet, "and Stonn would still be here".
Upon his return to the Enterprise, Spock declares his intention to surrender himself to Starfleet to face the consequences for killing his superior officer. But it turns out Kirk is alive, recovering in sick bay. Spock has a rare moment of outright joy in front of McCoy and Nurse Chapel. McCoy explains that he actually injected the Captain with a neuroparalyzer to simulate death. Spock tells them that when he thought he had killed the Captain, he lost all desire for T'Pring.
Due to T'Pau's high status, Starfleet grants permission for The Enterprise to divert to Vulcan unaware that Kirk has already done so.
The episode was written by acclaimed science fiction writer Theodore Sturgeon.
This is the first episode to feature the Vulcan greeting hand gesture, as well as the Vulcan mind-meld.
This is also the first episode to air with Ensign Chekov as a crew member, and one of the few episodes of the second season featuring both Sulu and Chekov in the same episode.
Spock is now referred to as a 'Commander' rather than 'Lieutenant Commander', suggesting that he has recently been promoted.
The episode is the first to feature the now classic Star Trek 'fight' music.