Turnabout Intruder (episode)
Dr. Janice Lester, a mad scientist, tries to take control of the Enterprise by switching bodies with Captain Kirk. (Series finale)

Summary

Teaser

The  answers a distress call from an archaeological expedition on Camus II and a landing party beams down. Captain Kirk finds that Dr. Janice Lester, whom he knows, is gravely ill, and Dr. Arthur Coleman is tending to her.

Lester is in bed and awakens just as Spock's tricorder picks up faint life-form readings. Lester becomes unquiet and Dr. McCoy suggests that Kirk stay with her while the others leave to investigate the readings.

When Kirk and Lester reminisce about their time together at Starfleet Academy, Lester is still resenting her inability to rise to a captaincy. When Kirk examines an apparatus in the room, Lester activates it. It traps Kirk into position on one side of it. Lester then rises from her bed and stands alongside Kirk on the apparatus and effects a life-entity transfer, each from one body into the other.

Act One

Lester (in Kirk's body) discloses to Kirk (in Lester's body) her plan to command the Enterprise, as well as her willingness to kill. Lester/Kirk starts to strangle Kirk/Lester but is interrupted as the others return. McCoy reports that the rest of the staff on the planet are dead of exposure to celebium, though Coleman says that this is unclear, a disagreement that will affect the choice of treatment. The survivors beam back to the Enterprise. Lester, in Kirk's body, orders that a medical team stand by in the transporter room for Kirk in Lester's body.

In sickbay, Lester/Kirk and Dr. Coleman discuss Kirk/Lester, whom they want to keep from reawakening. Coleman knows Lester's plans, and in fact knows both that celebium was the lethal agent and that Lester had caused the deaths by sending the personnel to where the celebium shielding was weak. On the surface of Camus II, Coleman had kept the rest of the landing party apart to give Lester time enough to kill Kirk, but he refuses to induce Kirk's death.

McCoy arrives and is surprised to see the captain in sickbay. Lester/Kirk transfers responsibility for the patient's care to Dr. Coleman, despite McCoy's strenuous protests. Kirk/Lester regains consciousness, but Coleman orders Nurse Chapel to administer a sedative.

Act Two
The impostor Kirk orders Sulu to execute a course change for a hospital on Benecia Colony, even though Spock points out that a course for Starbase 2 would provide a better radiation treatment without delaying the rendezvous with the  at Beta Aurigae. Lester/Kirk reacts sternly to being informed of the consequences of her/his orders.

The captain next meets with McCoy in Kirk's quarters, who defends his qualifications to treat Lester and has discovered that Coleman was relieved of duty as a chief medical officer on a starship due to severe incompetence. The captain says his decisions stand but McCoy uses his authority to order the captain to a medical examination based on "emotional instability and erratic mental attitudes since returning from that planet." The captain calls this revenge, but the confrontation is interrupted by a recall to the bridge.

In sickbay, Kirk/Lester again regains consciousness and calls for McCoy. Dr. Coleman says he is in charge and tells Chapel that Kirk's claims are symptoms of a paranoia that has been developing for six months. He tells Kirk, "You are insane, Dr. Lester."  He orders the nurse to keep Dr. Lester under constant sedation.

Act Three
Kirk, in Lester's body and working not to seem paranoid to Nurse Chapel, asks to meet with McCoy or Spock, but is alarmed to hear in passing of the course change ordered for the Enterprise. Chapel gives the patient a drink and leaves. After the nurse has gone, Kirk/Lester pours the drink onto the floor, breaks the glass and uses it to cut the restraints on his/her bed.

Nearby, McCoy discusses with Spock his plans to run tests on "Kirk". News of the captain's aberrant behavior is spreading around the ship, and both of them are convinced that a rapid-onset mental illness began during Kirk's brief time alone with Lester on Camus II. The patient approaches the two – but the captain had arrived a moment earlier. Lester/Kirk violently knocks Kirk/Lester unconscious and orders him/her to be placed in isolation with a twenty-four-hour watch.

Soon, however, Spock arrives at the cell to question the prisoner. Lieutenant Galloway concedes Spock's point that isolation orders have never applied to the Enterprises senior staff. Kirk/Lester calmly explains to Spock the technology of life-entity transfer, "accomplished and forgotten long ago on Camus II." When Spock protests that Starfleet requires objective evidence, Kirk describes events from their common past, such as their encounter with the Tholians and also the Vians, then finally, he invites the Vulcan mind meld. Performing, then breaking, the meld, Spock is convinced and asks Kirk?lester to come with him. When Galloway tries to block this, Spock disables him with a Vulcan neck pinch — but not before Galloway can call for backup.

The captain passes McCoy's physical, but McCoy insists on performing the Robbiani dermal-optic test to compare to a previous test. This, too, reveals nothing. Then they hear on the intercom that the prisoner has escaped. The captain goes to the cell, Spock surrenders, and the captain broadcasts throughout the ship a call for an immediate court martial of Spock on the charge of mutiny.

Act Four
The court martial convenes in a briefing room. Scott interrogates Spock, who describes his telepathic evidence that Kirk and Lester have exchanged bodies. Scott tells Spock that Starfleet Command will need more concrete proof than that. Later, McCoy testifies that the captain's physical and mental state are as they were when he assumed command of the Enterprise. Spock's logic compels Lester/Kirk to call Kirk/Lester out of isolation to testify. Lester/Kirk describes the life-entity transfer, but Kirk/Lester interrogates her/him in such a way so as to ridicule her/him.

Lester/Kirk accuses Spock of inventing the life-entity transfer controversy to assume the captaincy. Spock asserts his intent to reveal the truth and oppose the captain (i.e. Lester/Kirk). Lester/Kirk regards this as an overt confession of mutiny, but as she/he makes this clear, she/he sounds increasingly irrational. She/he declares a recess, followed immediately by the vote.

In the corridor, McCoy and Scott agree that the captain's (impostor) state of mind is unprecedented. Scott admits he never saw him "red-faced with hysteria" until now. Scott asks McCoy what the captain will do if they vote a ruling that Spock is innocent? They conclude that the captain will claim that they joined the mutiny ergo: "we'll have to take over the ship". Lester/Kirk is recording the conversation and extends the mutiny charge and orders the death penalty to them. Chekov and Sulu protest that the death penalty is expressly forbidden, except for General Order 4, which has not been violated by any Enterprise crew member. The enraged Lester/Kirk angrily orders that the other senior officers return to their posts, but imprisons McCoy, Scott and Spock. Lemli locks Kirk/Lester in a cell with a force field.

Lester/Kirk schedules a group execution on the hangar deck, with interment to take place on Benecia, but Sulu and Chekov take their hands away from their helm and navigation consoles in defiance. Unexpectedly, the life-entity transfer temporarily reverses, as Kirk/Lester senses it briefly in the holding cell. Lester/Kirk  runs to meet Dr. Coleman in the archaeology lab to tell him the transference is weakening. Coleman says the only solution is to quickly kill Lester's body but again refuses to do so personally. However, Lester/Kirk says Coleman is already complicit in many murders and now has no choice. Coleman gives Lester/Kirk a phaser and prepares a doubly lethal hypospray which he also gave the captain. They hurry to her cell, to kill Kirk/Lester before the transference wears off.

Lester/Kirk disables the cell's force field and orders Kirk/Lester to come out as he/she will be the first to be executed, lying that the prisoners would be moved to different cells — supposedly to prevent further conspiracy. But before Lester/Kirk can kill Kirk/Lester with the hypospray, the life-entity transference wears off completely and Kirk, now in his own body, successfully prevents the murder. Lester, in her original body, collapses into enraged hysterics over her total, and now permanent, defeat. Kirk lets Coleman accompany Lester back to sickbay to care for her and laments her bad decisions.

Log entries
 Captain's log, USS Enterprise (NCC-1701), 2269

Memorable quotes
"Your world of starship captains doesn't admit women."
 - Lester to Kirk, on Camus II

"I loved you. We could've roamed among the stars."
"We'd have killed each other."
"It might have been better."
 - Lester and Kirk, before their life-entity transfer

"Believe me, it's better to be dead than to live alone in the body of a woman."
 - Lester, inside Kirk's body

"Youth doesn't excuse everything, Dr. McCoy."
 - Lester, as Kirk, in the transporter room

"Love? Him?!? I loved the life he led. The power of a starship commander. It's my life now!"
 - Lester, as Kirk, to Coleman

"You are closer to the captain than anyone in the universe."
 - Kirk, as Lester, to Spock

"You claim that… that you are Captain James T. Kirk?"
"No. I am not Captain Kirk. That is very apparent. I claim that whatever it is that makes James Kirk a living being special to himself is being held here in this body."
"Oh. Well. However, as I understand it, I… am Dr. Janice Lester."
"That's very clever, but I didn't say it. I said, the body of James Kirk is being used by Doctor Janice Lester."
"A subtlety that somehow escapes me. I assume that this switch was arrived at by mutual agreement."
"No. It was brought about by a violent attack by Dr. Lester and the use of equipment she discovered on Camus II."
"Violence by the lady, perpetrated on Captain Kirk? I ask the assembled personnel to look at Dr. Janice Lester and visualize that historic moment. Can you, can you tell me why Dr. Janice Lester would agree to this ludicrous exchange?"
"Yes. To get the power she craved, to attain a position she doesn't merit by temperament or training. And most of all, she wanted to murder James Kirk, a man who once loved her. But her intense hatred of her own womanhood made life with her impossible."
 - Janice Lester, as James T. Kirk, and James T. Kirk, as Janice Lester – 

"You are not Captain Kirk. You have ruthlessly appropriated his body, but the life entity within you is not that of Captain Kirk. You do not belong in command of the Enterprise, and I will do everything in my power against you." 
 - Spock at his hearing, to Lester as Kirk

"You have heard the statements you put into the record. Do you understand the nature of it?"
"I do, sir. And I stand by it."
"It is mutiny!"
 - Lester, as Kirk, and Spock

"On the basis of these statements, I call for an immediate vote, by the powers granted to me as Captain of the Enterprise. A recess is declared, to be followed by a vote."
"Yes, sir. An immediate vote before our chief witness can be left to die on some obscure planet with the truth locked away inside of her."
"Silence! You will be silent!! A recess has been declared. There will be no cross-discussion. When I return, we will vote on the charge of mutiny. The evidence presented here is the only basis of your decision."
 - Lester, as Kirk, and Spock – 

"Doctor, I've seen the captain feverish, sick, drunk, delirious, terrified, overjoyed, boiling mad. But up to now I have never seen him red-faced with hysteria."
 - Scott to McCoy, outside the hearing room

"Headquarters has its problems, and we have ours. And right now, the captain of the Enterprise is our problem."
 - Scott, to McCoy

"We're talking about a mutiny, Scotty."
"Aye. Are you ready for the vote?"
"Yes, I'm… I'm ready for the vote."
 - McCoy and Scott, before returning to the hearing room

"The death penalty is forbidden. There is only one exception."
"General Order 4! It has not been violated by any officer on the Enterprise!"
 - Sulu and Chekov, on the death penalty

"The bridge is where you belong."
 - Scott to Kirk as Lester, in the brig 

"Oh, I'm never going to be the captain, never… kill him…"
"You are… you are as I loved you."
 - Janice Lester and Dr. Coleman

"I didn't want to destroy her."
"I'm sure we all understand that, Captain."
"Her life could have been as rich as any woman's. If only… if only…"
 - Kirk and Spock, speaking the last lines of the Original Series

Background information

Production timeline
 Similar story premise, "Turnabout" by Gene Roddenberry: early 
 Story outline by Gene Roddenberry: 
 Revised story outline: 
 Second revised story outline: 
 Third revised story outline: 
 First draft teleplay by Arthur Singer: 
 Second draft teleplay: early-
 Final draft teleplay: 
 Revised final draft teleplay by Fred Freiberger: 
 Additional page revisions by Freiberger: , , 
 Filmed:  – 
 Original airdate: , postponed from 
 First UK airdate:

Title, story, and script 
 Because  was canceled instead of coming to a natural end, and the idea of a series finale was not as popular in the 1960s, "Turnabout Intruder", despite being the series finale of TOS, is closer to a normal episode and does not have the "finale" touches.
 In James Blish's novelization of "Turnabout Intruder" in Star Trek 5, Dr. Arthur Coleman's first name is "Howard" – probably from an early draft of the script. At the end of the episode, Kirk muses about Janice Lester, "Her life could have been as rich as any woman's, if only… if only…" In Blish's rendition, Spock finishes the sentence, adding: "If only she had been able to take pride in being a woman."
 The set crew's nickname for this show was "Captain Kirk, Space Queen". (Star Trek Lives!, p. 176)

Cast 
 Uhura is the only regular character absent in this episode. The actress, Nichelle Nichols, had a singing engagement at the time and was unavailable, so was replaced by Barbara Baldavin as Lisa. 
 After two years on the series, Roger Holloway finally got to speak dialogue – all of two words: "Aye, sir." His character's name (Lemli) was the same as William Shatner's license plate at the time, a mixture of his daughters' names (i.e., Leslie, Melanie, and Lisabeth).
 Typically blonde, Christine Chapel appears with auburn hair in this episode, as well as previously, in . By the time of , her hair had re-darkened to its natural dark brown color.
 Lieutenant Galloway reappears in this episode, despite having been killed by Ronald Tracey in . He was credited as "Galoway" even though actor David L. Ross had been recast as Lieutenant  in  after the character of Galloway was killed off.
 Leonard Nimoy (Spock) and Majel Barrett (Nurse Christine Chapel and Number One) were the only actors to appear in both this episode and first pilot . Nimoy was the only actor to appear in every episode of the series. William Shatner appeared in every episode with the exception of "The Cage". Jeffrey Hunter, who had played Christopher Pike in the first pilot episode, died a week before "Turnabout Intruder" aired.
 The very last Enterprise crew member to be seen in the original series is Scotty. As he, Kirk, and Spock enter the turbo-elevator at the end of Act IV, a glimpse of his forearm, grasping the control handle, is visible before the doors close.
 In his The Star Trek Compendium, author Allan Asherman credited Sandra Smith as the only actor besides William Shatner to have "played" James T. Kirk. With the release of J.J. Abrams' , this was no longer true, as the film featured a "new" Kirk, played by Chris Pine, Jimmy Bennett, and an unidentified baby. Nevertheless, Smith still remains the only woman to have portrayed Kirk.

Sets and props 
 For story reasons, Janice Lester convalesces in a private, never-before-seen room down the corridor from sickbay.

Production 
 There is a detailed account of the filming of this episode in the  book Star Trek Lives!. Co-author Joan Winston had the opportunity to spend six days on the set while "Turnabout Intruder" was being shot. Winston wrote that Shatner was very ill with the flu at the time and had considerable difficulty in picking up and carrying Sandra Smith, the actress who played Dr. Lester, for take after take. At one point, he said, "You know I love you, baby, but you've got to lose about six inches off that ass," which brought down the house.
 Joan Winston also recalled many amusing anecdotes that took place during the shooting. For example, William Shatner flubbed the line, "Spock, give it up. Come back to the Enterprise family. All charges will be dropped. And the madness that overcame all of us on Camus II will fade and be forgotten." Instead, he blurted out, "Spock, it's always been you, you know it's always been you. Say you love me too."
 Shatner clashed with director Herb Wallerstein, when Wallerstein wanted Kirk to exit a scene via what was established as a wall. 
 During the first three filming days, pre-production was underway for the 25th episode of the season, "The Joy Machine", to be directed by William Shatner. However – as reported by Winston – on the fourth day of filming, Monday , Gene Roddenberry came to the set and informed Shatner that the series was canceled by NBC, and his directorial debut wouldn't be produced. Despite suffering from the flu, and saddened by the news, Shatner performed his scene perfectly. (These Are the Voyages: TOS Season Three, pp. 637)
 The rest of the cast and crew were notified of NBC's decision at the end of the day by associate producer Gregg Peters, making a formal announcement. (These Are the Voyages: TOS Season Three, pp. 637-638)
 Pro football player , just starting his acting career at that point, visited the set the same day, and was escorted by Roddenberry. Simpson witnessed the aforementioned event with Shatner on the bridge set. Regarding Shatner's professional demeanour, Roddenberry told him, "You have just seen an actor at work.". (These Are the Voyages: TOS Season Three, pp. 637)
 Even as filming was wrapping up, crew members were dismantling the Enterprise sets. Filming was completed on . Production went one day over schedule, resulting in seven filming days. (Inside Star Trek: The Real Story)
 The final scene ever filmed for the original series was of William Shatner and Sandra Smith in front of the alien transference machine. (These Are the Voyages: TOS Season Three, p. 641)

Music 
 This installment opens with the same music cue as the previous three episodes, taken from the opening titles of . In common with the immediately prior entry to this one, this episode ends with the closing music cue from .

Reception 
 A scheduled airdate of  was preempted by news coverage of the death of former president Dwight D. Eisenhower. This episode was not aired until  for that reason. Due to being rescheduled, the episode missed the deadline for Emmy nominations. (Smithsonian magazine,  issue, p. 59) It was the last installment of the franchise to air in the 1960s.
 Although the BBC's first run airdate order during - was very different to NBC's, this was also the final episode screened in the UK, on .
 Bjo and John Trimble were very impressed by this episode. "[It] was very good; it might have won an Emmy for William Shatner," they appreciatively speculated. (Smithsonian magazine,  issue, p. 59)
 Critic Scott Mantz considered the episode's final moments to be significant. "There is something somewhat apropos," he said, "about the last words of the last episode, 'Turnabout Intruder': 'Her life could have been as rich as any woman's. If only… If only.' And then Kirk walks off." (Smithsonian magazine,  issue, p. 59)
 The episode drew Nielsen ratings of only 8.8, in contrast to rival shows  on CBS and  on ABC, which gained ratings of 14.7 and 15.2 respectively, a drop of over 50% since the show premiered.
 Cultural theorist Cassandra Amesley states that this episode is "agreed to be one of the worst Star Trek episodes ever shown" by Star Trek fans. Brenton J. Malin sees the episode as a reactionary response to the radical feminism of the late 1960s. Dr. Lester is a "caricature and condemnation of the feminism of the late 1960s, evoking a fear of powerful, power-hungry women… The message seems clear: women want to kill men and take their jobs, but ultimately they can't handle them."
 David Greven has a more positive view of the episode, even referring to it as "moving". He calls it the "infamous last episode" of the original series, in part because of the "campiness" of Shatner's performance when portraying himself as a female in a male's body, but also because of the sexist premise that "female desire for power was a clear sign of insanity". While accepting that "the sexism of the episode is indisputable", he argues that the exploration of the idea that man can inhabit a woman's body, and vice versa, gives the episode a "radical" dimension, which he claims implies the interchangeability of gender and sexual identity.
 In 2017, this episode was rated by ScreenRant as the 4th worst episode of the Star Trek franchise, including later spin-off series. A ranking of every episode of the original series by Hollywood placed this episode in last place. 
 In 2017, Den of Geek ranked this episode as the 7th worst Star Trek episode of the original series.

 Continuity 
 The name of the planet Benecia is pronounced differently in this episode than it was in , i.e., "beh-NEE-shee-a" as opposed to "beh-neh-SEE-a".
 In this episode, Kirk mentions the events of two previous episodes ( and ) to Spock.
 Starfleet's General Orders appear to have changed by this time. Sulu and Chekov say that only violating General Order 4 warrants the death penalty. In , though, it was stated that violation of General Order 7 (the ban on contact with Talos IV) was the "only death penalty left on the books."
 Although this was the last episode of the Original Series to be filmed and aired, this episode has a lower stardate than the previous episode, .
 Janice Lester, in the body and voice of Captain Kirk, makes a captain's log entry, discussing the status of the conspiracy.
 As a subtle hint that all is not right with Kirk, whenever Lester/Kirk refers to himself, he uses the more formal "Captain Kirk" instead of the usual "Kirk". (e.g., "Captain Kirk to the Enterprise" instead of the usual "Kirk to Enterprise," "Captain Kirk out" instead of "Kirk out," etc.)
 This episode is subtly referenced in . In that episode, Jean-Luc Picard mentions in his captain's log that "The Enterprise has bypassed its scheduled archaeological survey of Camus II…", referencing the same planet that this episode begins on. This was mentioned because, with the airing of its eightieth episode, "Legacy",  officially "bypassed" the series-run of Star Trek: The Original Series. ()
 In this episode Janice Lester states, "Your world of starship captains does not admit women." In fact, the entire basis of the episode is that Janice Lester wanted to be a starship captain so badly (but could not because of her gender) that she switched bodies with and tried to murder Captain Kirk. This was later contradicted by  and . In , set in 2154, the second warp-5 ship to be launched in the NX Program, the  is captained by a woman, Captain Hernandez. In Discovery, set a decade prior to this episode, Captain Philippa Georgiou is established not only as the captain of the , but to be among the most decorated Starfleet captains (in ). This, however, is not necessarily a contradiction. Lester's line "Your world of starship captains does not admit women" might not have been intended to mean "Starfleet doesn't allow women starship captains," but rather could have meant that Kirk's world as a starship captain did not (and, by a necessity she refused to appreciate, could not) include her, since they were talking about their relationship, not Starfleet.

Remastered information
 This was the second to last episode of TOS to be remastered, and the second to last to be aired.
 The remastered version of "Turnabout Intruder" ends with the Enterprise flying toward a colorful nebula, to artistically signify the episode as being the last of the TOS series.

Video and DVD releases
 Original US Betamax release: 
 UK VHS release (two-episode tapes, CIC Video): Volume 40, catalog number VHR 2436,  (This volume is a three-episode tape to close out the series.)
 US VHS release: 
 UK re-release (three-episode tapes, CIC Video): Volume 3.8, 
 Original US DVD release (single-disc): Volume 40, 
 As part of the TOS Season 3 DVD collection
 As part of the TOS-R Season 3 DVD collection.
 As part of the Star Trek: Fan Collective - Alternate Realities'' collection

Links and references

Starring
 William Shatner as James Kirk

Also starring
 Leonard Nimoy as Mr. Spock
And
 DeForest Kelley as Dr. McCoy

Guest stars
 Sandra Smith as Janice Lester 
 Harry Landers as Dr. Coleman 
 James Doohan as Scott
 George Takei as Sulu
 Walter Koenig as Chekov
 Majel Barrett as Nurse Chapel
 Barbara Baldavin as Communications Officer
 David L. Ross as Lt. Galoway [sic]
 John Boyer as Guard

Uncredited co-stars
 Tom Anfinsen as Medical technician 1
 William Blackburn as Hadley (stock footage)
 James Drake as a security guard
 Roger Holloway as Lemli
 Unknown actors as
 Medical technician 2
 Security guard

References 
2265; 2267; administrative duties; administrative incompetence; agony; "all right"; ambition; area; archaeological expedition; arm; arrest; "as usual"; "as yet"; attack; "at the moment"; attention; authority; nightmare|bad dream; behavior; belief; Benecia; Benecia Colony; Beta Aurigae; binary system; blood count; blood pressure; body; body function; "Bones"; brig; "by any means"; Camus II; Camus II natives; Camus II staff; case; celebium; celebium shielding; cell; chance; ; chief medical officer; choice; civilization; Coleman's former post; color wavelengths; confidence; consciousness; conspiracy; conversation; coordinates; cooperation; corridor; course; court; criticism; death; death penalty; debt; delirium; delusion; demotion; destination; diagnosis; disorder; distress call; dosage; drunk; efficiency; emergency; emotional instability; emotional stress; emotional structure; event; evidence; examination; execution; exercise table; expedition; expedition surgeon; experience; exposure; eye; fact; family; fever; general court martial; General Order 4; glands; gravitational study; guard; hangar deck; "hard feelings"; hate; health; ; heart; hysteria; "if only"; imprisonment (aka internment); indignity; individual; "in fact"; insanity; instruction; interspace; "in charge"; "in the pink"; investigation; isolation; jealousy; judge; kidney; knowledge; landing party; leader; life-entity transfer; line of duty; liver; logic; malpractice; maximum speed; mechanical device; medical blunder; medical facility; medical team; medical test; memory; mental attitude; mental state; metabolic rate; meter; Milky Way Galaxy; Minara; mind; mind meld; minute; mission; month; motive; murder; murderer; mutineer; mutiny; mutual agreement; nail file; NGC 602; objective test; "of course"; office; "on the double"; opinion; opportunity; orbit; order; "out in the open": paranoia; patient; permission; person; phaser; phenomenon; physical condition; physical strength; place; plan; ; ; ; prisoner; problem; promotion; protection; pulse; question; radiation; radiation poisoning (aka radiation illness/radiation damage); recess; record; rendezvous; report; representative; result; revenge; risk; Robbiani dermal-optic test; room; ruins; scanning range; scientific analysis; scientist; search; security guard; sedation; sedative; senior officer; sentence (law);  (linguistics); ship surgeon; shock; smothering; "so be it"; "so far"; specialist; speed; star; Starbase 2; Starfleet; Starfleet Command; Starfleet Headquarters; Starfleet Regulations; starship; starship captain (aka starship commander); "state of mind"; statement; "stick in his craw"; story; subject; suggestion; supervision; Surgeon General; survivor; suspicion; symptom; tape; telepathy; temperament; testimony; Tholian sector; thought; time; "time is of the essence"; training; treatment; tricorder; truth; unconscious; "under arrest"; universe; Vians; violence; visit; vote; Vulcan neck pinch; warp factor; ; wavelength; witness; womanhood; year; youth

Unreferenced material 
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TOS episodes