(written from a Production point of view)
On an isolated asteroid, Kirk finds Zefram Cochrane, inventor of the warp drive, who has been missing for 150 years.
Kirk, Spock, and McCoy are ferrying Federation Commissioner Nancy Hedford back to the USS Enterprise. The commissioner, who has been called upon by the Federation to prevent a war on Epsilon Canaris III, has developed Sakuro's Disease, an extremely rare life-threatening illness, and must be removed to a medical facility for treatment. The commissioner is bitter at what she regards as incompetence in the Federation Medical Department, which she believes should have properly prepared her.
En route (shortly past point 3, on course 201 Mark 15), the shuttlecraft Galileo encounters a phenomenon that Spock describes as "vaguely like a cloud of ionized hydrogen, but with strong erratic electrical impulses". Moving at warp speed, it quickly envelops the shuttlecraft and disables its systems. The craft is pulled to course 98 Mark 12, towards the Gamma Canaris region.
There, it is soft-landed on an iron-nickel planetoid with a standard oxygen-nitrogen atmosphere and standard gravity – a place entirely suited for Human life. Examining the shuttlecraft, Spock discovers something that should be impossible: nothing is damaged and yet nothing works. McCoy notes that the gaseous cloud they encountered in space seems to be here, on the surface. Then a loud "hallooooooo" breaks the stillness. Someone else is here – a young man who quickly joins the stranded group. He introduces himself simply as Cochrane. He tells the officers that a damping field prevents some technology here from working. But he denies knowledge of the force that brought the shuttlecraft here.
Kirk and McCoy find this man familiar, somehow, but cannot quite place him. Cochrane shows his visitors to his home, decorated with instruments Kirk regards as antiques. Ominously, Commissioner Hedford has developed a fever, the first symptom of her illness.
Finally, Kirk presses Cochrane, and learns about the Companion. This is what he calls the strange creature that brought the Galileo here. Kirk asks him his first name, and then realizes why Cochrane seems so familiar: he is Zefram Cochrane of Alpha Centauri, inventor of space warp drive. Cochrane was old, and knew he wanted to die in space. So he took a spacecraft and left his home on Alpha Centauri for parts unknown. The Companion found him, reversed his aging process, and has maintained him here ever since. Cochrane is responsible for the abduction of Kirk and his party via communicating his loneliness to the Companion; he had thought that the Companion would simply release him. During the discussion Hedford suddenly starts crying and yelling incoherently, forcing McCoy to sedate her with a hypospray and place her in Cochrane's bed.
Kirk asks Spock to attempt to repair the Galileo. While doing so, with a trident scanner, the Companion appears there, directly behind him. Curious, he touches it, and receives an electrical shock that destroys the scanner and knocks him out cold. The circuitry of the Galileo bursts into flame; the Companion is taking no chances.
Cochrane agrees to summon the Companion, to see if it can help Commissioner Hedford. Kirk asks him how he will summon the Companion and Cochrane replies "I just sort of clear my mind, and it comes." While observing the Companion with Cochrane, McCoy and Kirk notice the apparent, almost Telepathic communion, and find it cannot be minimized to anything less than love. Unfortunately, Cochrane learns that the Companion cannot do anything to help Commissioner Hedford.
McCoy discovers Spock; the encounter has left Spock with a new insight: the Companion is largely made of electricity. McCoy asks Spock if he is correct in surmising that something made up of electricity can be shorted out. Spock confirms this and later constructs a mechanism to scramble electrical impulses; with this, Kirk intends to disable or destroy the creature, so that the Humans may depart. Cochrane now has reservations; he doesn't want the creature killed, saying "we've been very close in a way that's hard to explain". Kirk overwhelms him with the force of his personality, though Cochrane understands their perspective. Unhappy at being forced into the role of a Judas goat, Cochrane nevertheless agrees to summon the creature. Spock throws the switch, and discovers that his mechanism is sufficient only to irritate the creature. It attacks Kirk and Spock, choking them. McCoy yells at it to stop before it kills his friends.
Despite McCoy's pleas, the Companion continues to attack Kirk and Spock. Cochrane eventually comes to and calls off the Companion. McCoy suggests to Kirk he is thinking too much like a soldier, not a diplomat. Trying the carrot instead of the stick approach, Kirk decides that they will communicate with the creature instead using the universal translator.
Nearby, the Enterprise searches for the now long overdue shuttlecraft. Finally, at 210 Mark 40, the sensors detect a strong antimatter particle concentration. Lacking evidence that the shuttlecraft has been destroyed, Scott elects to follow this tenuous course.
On Gamma Canaris, Spock has completed modifying the universal translator from the Galileo so Kirk can communicate with the Companion. Kirk begins by saying "We wish to talk to you" and the Companion replies with "How can we communicate? My thoughts... you are hearing them. This is interesting" in a feminine voice. From the voice, Kirk surmises that the Companion is female, casting her relationship with Cochrane in an entirely new light. Kirk implores the Companion to permit their departure, but she is adamant; to her, the safety and health of Cochrane is the only important goal. And to ensure that, she intends to keep the shuttlecraft crew here, forever.
Cochrane is dismayed to discover the truth behind the dynamic that exists between himself and the Companion. He finds it repulsive, disgusting even, and feels used. Kirk, Spock and McCoy do not understand his parochial attitude. For her part, the Commissioner – who is now barely conscious and close to death, but has regained some level of lucidity – is baffled by someone who, offered love, rejects it. The great regret of her life, as it draws near its end, is that she has never been loved.
The Enterprise continues its search. Sulu has discovered an asteroid field containing 7,000 bodies in sizes ranging from A to M. Thirty percent of them have atmospheres in types ranging from H to M. The search will be a long one, but Scott remains convinced by the lack of evidence that the shuttlecraft landed safely somewhere, and he is prepared to search every asteroid if necessary.
Kirk tries new tactics. First, he tries to convince the Companion that without obstacles to overcome, the Humans will weaken and die. When that fails, he tries to convince the Companion that there can never be real love, because it and Cochrane are too different. The Companion considers this, and then disappears. Kirk's hope is that the Companion will release Cochrane and his party – love expressing itself as sacrifice – but this is not her choice. Instead, moments later, an apparently healthy Nancy Hedford appears in the door of Cochrane's small home, her voice now gently echoing.
The Companion has joined with Hedford, sacrificing her powers and immortality to become Human, and experience life with Zefram Cochrane as a Human woman would. Cochrane is reluctant, but becomes enthusiastic, promising to show her the galaxy now that he can. Sadly, she tells him that she cannot leave; her life emanates from this small planetoid. Just as he must eat, so she must remain here or perish in a short march of days. Cochrane cannot bring himself to leave her, and elects to remain behind. He asks Kirk to keep his existence a secret, a request Kirk grants. Spock observes that Cochrane and Hedford will now live out a normal life span without immortality – a condition that both of them accept as inevitable and uniquely Human. McCoy fears that they have failed to stop the war on Epsilon Canaris III, but Kirk gives him relief that the Federation can surely find “another woman, somewhere, who will stop that war.”
- "Ship's log, stardate 3219.8. Lieutenant Commander Scott recording in the absence of Captain Kirk. A shuttlecraft bearing the captain, the first officer, Chief Surgeon McCoy, and Assistant Federation Commissioner Hedford is now definitely overdue for a rendezvous with the Enterprise. We are attempting to backtrack it."
- "Ship's log, stardate 3220.3. Lieutenant Commander Scott reporting in lieu of the captain and the first officer. We are continuing our search for the missing shuttlecraft."
"You're food to a starving man."
- - Cochrane to Hedford, as they are formally introduced
"I could even offer you a hot bath."
"How perceptive of you to notice that I needed one."
- - Cochrane and Hedford, as she ridicules his hospitality
"You wear your age very well."
- - Spock, complimenting Cochrane after realizing he is Zefram Cochrane
"Immortality consists largely of boredom."
- - Cochrane, after Kirk asks him if he wants to leave the planet
"What was it they used to call it? The Judas goat?"
- - Cochrane, before he baits the Companion
"Maybe you're a soldier so often that you forget you're also trained to be a diplomat. Why not try a carrot instead of a stick?"
- - McCoy to Kirk, on how to handle the Companion
"It's a big galaxy, Mister Scott."
- - Uhura, as the Enterprise searches for the missing shuttlecraft
"The idea of male and female are universal constants."
- - Kirk, explaining to Cochrane that the Companion is female
"You're not a pet. You're not a specimen kept in a cage. You're a lover."
- - McCoy, explaining to Cochrane his relationship with the Companion
"But I've never been loved. Never. What kind of life is that? Not to be loved, never to have shown love? And he runs away from love."
- - Hedford, on Cochrane's resentment toward the Companion
"This is loneliness. Oh, what a bitter thing."
- - The Companion as Hedford, after Cochrane recoils from her advance
"I can't leave her. I love her. Is that surprising?"
"Not coming from a Human being. You are, after all, essentially irrational."
- - Cochrane and Spock, on Cochrane's decision to stay with the Companion
Story and script
- Bantam Books published a series of novelizations called "foto-novels," which took photographic stills from actual episodes and arranged word balloons and text over them, to create a comic book formatted story. The fifth installment was an adaptation of this episode and featured an interview with Elinor Donahue.
- This is the only episode in the first two seasons in which Captain Kirk is not on the Enterprise at any time during the plot. Likewise, the Enterprise does not appear until twenty-seven minutes into the episode. In four third season shows, Kirk also spends the entire episode off-ship: "The Paradise Syndrome", "Plato's Stepchildren", "Whom Gods Destroy", and "All Our Yesterdays".
- In the first draft script, Scott is also on board the shuttlecraft (here called the Edison) with Kirk, Spock, McCoy, and Hedford. It was originally he who was to encounter the Companion while attempting to repair the shuttlecraft. 
- In the first draft, the Enterprise is temporarily commanded by Sulu, and the helmsman is an officer with an African background named Lieutenant Ackrumba.  The character later appeared in the novel Mission to Horatius.
- The first draft script ends with a joke: as the landing party leaves the planetoid, Spock wonders if Cochrane is a bigamist, by having two entities in the same body for his partner. Kirk assures him that this is nonsense. 
- A Gold Key Comics comic book was released as a sequel to this episode, #49: "A Warp in Space".
- This is the first story to feature Zefram Cochrane, inventor of warp drive and an important figure to Federation history. He later re-appeared in Star Trek: First Contact and ENT: "Broken Bow", played by James Cromwell.
- The Companion was designed by future Star Wars Oscar-winner Richard Edlund at Westheimer photographic effects company. (Star Trek Encyclopedia (? ed., p. ?)) The sparkling effects of the Companion was reused in "The Apple" when the Enterprise fires phasers at Vaal, and again in "Obsession" inside of the deadly vampire cloud.
- The episode's preview includes a take not used in the final episode, during which Hedford tells McCoy that she doesn't want to die. She does say this in the episode, before explaining that she has not had love in her life, but the scene is filmed as a close-up instead.
- The shuttlecraft mock-up is not the same as the set used for the interiors of the Galileo. Kirk and company are all crouching as they emerge from the ship, yet the shuttlecraft interior set had a lot more headroom.
- The scenes of Cochrane communicating with the Companion were all shot at one time. The set was then completely redone with his house added for all of the sequences with Kirk and company. The inconsistencies between the two versions of the same set can be seen in alien trees that are near Cochrane in one view and absent in the next.
- Symbolically, the colored patterns in the scarf worn by the Commissioner are identical to the patterns in the energy field of the Companion. This is shown clearly as she looks at Cochrane through the scarf near the end of the episode. This wasn't scripted or even intended by the production staff. Director Ralph Senensky came up with the idea on the set, calling it "one of those wonderful freak accidents that happen".  The inspiration was a scene in "The Escape", a 1966 episode of The F.B.I., also directed by Senensky. 
- A few scenes featuring Elinor Donahue had to be re-shot, because the original film negatives were damaged and couldn't be used. Portions of the planet set had to be rebuilt, since other episodes were shot there by that time, using different sets. Meanwhile, Donahue got pneumonia and lost ten pounds. To hide this, they put Hedford's scarf around her neck and upper body. However, her weight loss is still visible on her face.  The re-shots were not directed by Ralph Senensky. 
- To give an illusion of open space to a confined stage set, wide angle lenses were used. Although Glenn Corbett appears to be hundreds of yards away when he first runs toward the shuttle, he is much closer. Strategically placed rocks also allowed the camera to be very far away without seeing the edges of the set.
- A drawback to the use of a wide angle lens is evident in the scene where actor Corbett first approaches the shuttlecraft. Accent lights on top of the set's background are clearly visible along the top of the "sky" as the camera pans to the right when following Corbett's path. At the end of the shot the black edge of the set is clearly visible behind the shuttlecraft.
- In a rare effect, slowly moving "clouds" were blown in from hidden vents, adding a touch of reality to the usually static planet set. This was also used in "Obsession".
- A view of the starship from dead center in front of the saucer section is used only in this episode.
- All the footage of the shuttlecraft in outer space was reused from "The Galileo Seven", some with the Companion animation added in post-production.
- The planet used as Gamma Canaris N (a purple color-corrected version of the planet created for "Operation -- Annihilate!", portraying Deneva) is reused in subsequent episodes, representing the Halkan homeworld in "Mirror, Mirror", Omega IV in "The Omega Glory", and Holberg 917G in "Requiem for Methuselah".
- This was George Duning's first Star Trek score, the strength of which got him rehired for many more assignments, including "Patterns of Force", "Return to Tomorrow", "And the Children Shall Lead", "Is There in Truth No Beauty?", and "The Empath". Portions of the score were heard again throughout the season, but the love themes were reused only once more, in "The Gamesters of Triskelion".
- Walter Koenig (Pavel Chekov) does not appear in this episode.
- Elizabeth Rogers, uncredited for some reason for her voice work as the Companion, returned to the series two times as communications officer Lt. Palmer.
- The original voice of the Companion was too emotionless and robotic, and all of her dialogues had to be re-recorded by another actress (apparently Rogers). 
- Elinor Donahue recalled about this episode, "I remember watching it at home. And I am quite often nervous about watching something I'm in because there is nothing you can do about it once it's out there. But I was very pleased with it; very happy." (These Are the Voyages: TOS Season Two, p. 72)
- Ralph Senensky named this episode as his favorite among those he directed.  Senensky recalled, praising the work of Gene Coon, "I just thought the script was absolutely wonderful. As I remember Gene [Coon], he was the least author-y type of person. He just didn't seem like an author. He didn’t present that kind of sensitivity that his writing had expressed. It was just a deep, deep script and scene after scene had so many angles to come at it from. It was a complex script." 
The remastered version of this episode premiered in syndication the weekend of 3 November 2007. It featured new shots of the Galileo and the Companion in space, replaced a foreground rock with a shot of the sky in Cochrane's initial appearance, and included the shuttle returning to the Enterprise in the closing shot. Curiously, the remastered version of the planetoid matches the purple sky of the sound stage less than the original. The original planetoid was all purple while the remastered version is brown with only a slight purple atmosphere.
- Story outline by Gene L. Coon: 7 April 1967
- First draft teleplay: 14 April 1967
- Second draft teleplay: 19 April 1967
- Final draft teleplay: 21 April 1967
- Revised final draft: 3 May 1967
- Additional page revisions: 8 May 1967, 12 May 1967, 13 May 1967, 17 May 1967
- Filmed: 11 May 1967 – 19 May 1967
- Day 1 – 11 May 1967, Thursday (Half Day) – Desilu Stage 10: Ext. Gamma Canaris surface
- Day 2 – 12 May 1967, Friday – Desilu Stage 9: Int. Shuttlecraft, Bridge
- Day 3 – 15 May 1967, Monday – Desilu Stage 10: Int. Cochrane's home
- Day 4 – 16 May 1967, Tuesday – Desilu Stage 10: Int. Cochrane's home
- Day 5 – 17 May 1967, Wednesday – Desilu Stage 10: Int. Cochrane's home, Ext. Outside Cochrane's home
- Day 6 – 18 May 1967, Thursday – Desilu Stage 10: Ext. Gamma Canaris surface
- Day 7 – 19 May 1967, Friday (Half Day) – Desilu Stage 10: Ext. Gamma Canaris surface
- Score recording, 28 June 1967
- Original airdate, 10 November 1967
- Rerun airdate, 19 July 1968
- First UK airdate 11 May 1970
Video and DVD releases
- Original US Betamax release: 1986
- UK VHS release (two-episode tapes, CIC Video): Volume 17, catalog number VHR 2329, release date unknown
- US VHS release: 15 April 1994
- UK re-release (three-episode tapes, CIC Video): Volume 2.1, 3 February 1997
- Original US DVD release (single-disc): Volume 16, 19 September 2000
- As part of the TOS Season 2 DVD collection
Links and references
- William Blackburn as Hadley (stock footage)
- Jeannie Malone as a operations division yeoman
- Eddie Paskey as Leslie
- Elizabeth Rogers as the Companion (voice)
- Ron Veto as Harrison (stock footage)
- Unknown actor as a command division lieutenant
2030; 2119; affection; "all right"; "all the best"; Alpha Centauri; animal; antimatter; antique; argon; "as a matter of fact"; Assistant Federation Commissioner; asteroid; asteroid belt; atmosphere; "at the moment"; attitude; automatic scanner; bath; bearing; blindness; blood pressure; body; body temperature; "Bones"; boredom; brain wave pattern; cage; cane; cannibalism; captivity; carrot; chance; chief surgeon; choking; chronological age; cities named after Cochrane; Class M; classroom; climate; cloud; Cochrane's home; Cochrane's ship; commissioner; computer central; congruent lifeform; contact; coordinates; course; crash landing; creature; dampening field; day; death; debris; decency; degree; density; device; diplomat; distance; Earth; earth; electric shock; electrical impulse; electricity; electronic scrambler; element; emotion; emotional reaction; English language; entity; Epsilon Canaris III; estimate; estimated time of arrival (ETA); "excuse me"; existence; "eye-opener"; "face up to it"; Fahrenheit; Federation; feeling; feet; female; fever; field; fig tree; first officer; first name; fodder; frequency; full alert; Galileo; Gamma Canaris N; Gamma Canaris N sun; Gamma Canaris region; garden; gas; gender; grammar; gratitude; gravity; hammer; hand; handshake; heat; hello; heart; hijack; hiking; home; hospital; hour; Human (aka Earth people); hydrogen; immortality; "in fact"; inoculation; intelligent life; "in view of"; ion; iron; job; joy; Judas goat; kiss; knowledge; krypton; life; light; logic; loneliness; love; lover; Maker of All Things; male; marooning; matter; medical branch; medical facility; Milky Way Galaxy; million; mind; minute; monster; morality; name; nature; nickel; nitrogen; neon; non-verbal communication; "not a chance"; "not a word"; "of course"; "off the beaten path"; opportunity; "out of circulation"; "out of style"; overload; owner; oxygen; parochial; pattern; percent; pet; phaser; physical age; physicist; place; planet; planetoid; planets named after Cochrane; pod; "point of view"; power relay; power system; prisoner; probability; propulsion; question; range; rejuvenation; relationship; rendezvous; respiration; ridge; "right down your alley"; risk; Sakuro's Disease; scarf; scientist; search; sensor; shelter; shuttlecraft; shuttlecraft bay; size; soldier; space; space warp; species (aka race); specimen; spherical sweep; spirit; standard orbit; "stand by"; Starfleet; Starfleet Medical; starship; stick; story; sun; surface; switch; symbiosis; "take it easy"; "take my word"; Telepathy; temperature; "thank you"; theory; thing; thought; thousand; tolerance level; tool; toy; tractor beam; trick; tricorder; trident scanner; university; universal translator; vegetable; voice; voltage; Vulcan; war; water; weapon; will; year; zookeeper
- "Metamorphosis" at StarTrek.com, the official Star Trek website
- "Metamorphosis" at Memory Beta, the wiki for licensed Star Trek works
- "Metamorphosis" at Wikipedia
- "Metamorphosis" at MissionLogPodcast.com, a Roddenberry Star Trek podcast
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"Journey to Babel"
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"The Deadly Years"