After taking an accidental overdose of cordrazine, Doctor Leonard McCoy goes back in time and changes history.
The USS Enterprise passes through violent time distortions surrounding a strange planet. During one of these events, the center console on the bridge sparks and Lt. Sulu is injured. Doctor McCoy is called to the bridge for emergency first aid. He prepares a hypo of cordrazine, warned by Kirk that it is "tricky stuff".
After Sulu is revived, the ship rocks violently as it passes through a very heavy time displacement. McCoy falls on the hypo and is injected with an extreme overdose of the red liquid. He shouts in pain. The negative effects of the drug push him to paranoia, and he is convinced that he is at risk of death from "murderers" and "assassins". He breaks free from Spock's hold on him and escapes the bridge. Kirk scrambles security teams.
- "Captain's log, supplemental entry. Two drops of cordrazine can save a man's life, a hundred times that amount has just accidentally been pumped into Dr. McCoy's body. In a strange, wild frenzy, he has fled the ship's bridge. All connecting decks have been placed on alert. We have no way of knowing if the madness is permanent or temporary, or in what direction it will drive McCoy."
Kirk, Spock, Uhura, Scott, Galloway and another security officer beam down to look for McCoy. During their search, Spock and Kirk discover the source of the time displacement. It is a rough, egg-shaped ring. After a discussion between Spock and Kirk, the portal introduces itself as the Guardian of Forever, and as being, itself, its own beginning and own ending. It begins to display the history of Earth through the center of the ring. A curtain of mist descends across the images.
McCoy is discovered and subdued by a Vulcan nerve pinch. After the struggle, Kirk and Spock return to the portal. Spock is upset that he is not recording the events visible through the portal. He begins recording. McCoy awakens from his unconsciousness and learns enough to realize he can escape through the Guardian. He races past Spock and Kirk, through the Guardian, and into Earth's past. Then Uhura notes that contact with the Enterprise has been lost. The Guardian explains that history has been altered, resulting in the ship's absence.
- "Captain's log, no stardate. For us, time does not exist. McCoy, back somewhere in the past, has effected a change in the course of time. All Earth history has been changed. There is no starship Enterprise. We have only one chance. We have asked the Guardian to show us Earth's history again: Spock and I will go back into time ourselves, and attempt to set right whatever it was that McCoy changed."
Kirk and Spock are forced to enter the portal in an attempt to stop McCoy from changing history. Before leaving, Kirk orders Scotty, should they fail to correct history, to use the portal to return to the past so that at least they will remain alive. Spock uses his tricorder recording to estimate the appropriate time for their leap.
The two arrive on Earth in the United States of America in 1930. They are obviously out of place with their Starfleet uniforms and Spock's pointed ears. Kirk steals clothes from a fire escape to aid in their disguise. A policeman catches the two in the act, and after a poor excuse for the theft, and Spock's ears, they subdue the officer with the Vulcan nerve pinch. With other law enforcement hot on their heels, they duck into a soup kitchen called the Twenty-First Street Mission. There they meet Edith Keeler, the woman who runs the shelter.
Upon explaining to her that they didn't have any money, Edith offers them a job cleaning up around the mission at a pay-rate of 15¢/hr for 10 hours a day. After lunch, Edith compliments Kirk on the work he and Spock did in the basement and asks if they have a flop for the night. She informs him that there's a vacant room where she lives for $2/week.
Unable to view the video acquired on the tricorder to determine McCoy's arrival date and the cause of the timeline contamination, the two spend their combined salaries on supplies to modify its rate of playback. After their third day of work, Kirk returns from shopping with radio tubes, wires and other items. Spock is noticeably frustrated at the lack of technology in the 1930s. He spends many hours building circuits and connections. Eventually, after several setbacks, the tricorder reveals its wealth of information. Spock sees Edith Keeler's imminent obituary. Then he plays the recording for Kirk – and they see a report about Edith Keeler's meeting with United States President Franklin D. Roosevelt six years hence. She cannot have two futures; they've discovered the point where McCoy altered the past. But did he save her? Or kill her? And how?
"What if Edith Keeler must die?" Spock asks the troubled Kirk.
McCoy arrives approximately one week after Kirk and Spock. His face is mottled and green from the effects of the cordrazine. He shouts, "Assassins! Murderers! Murderers! Assassins!", from his paranoia. He meets a homeless man who frequents the 21st Street Mission and questions him about their location, time, planet, and constellations. His shock at the unfamiliar world, combined with the side effects of the drug, forces McCoy into unconsciousness. The homeless man searches McCoy and finds his phaser. While trying to assess its value, the man engages the device and annihilates himself along with the weapon.
After regaining consciousness, McCoy finds some of the effects of the cordrazine have worn off and he makes his way to the shelter, where Edith helps him into a room where he can rest. Spock narrowly misses seeing him in the lunch room.
With more work, Spock concludes that McCoy changed history by saving Edith Keeler's life. Keeler went on to organize a peace movement that delayed the United States' entry into World War II – and Germany was able to complete its heavy water and rocket experiments. With atomic bombs, and rockets to carry them, the Nazis conquered the world.
Kirk admits that he is in love with Edith Keeler. Spock informs him, "Edith Keeler must die."
The effects of the drug slowly wear off, and McCoy eventually has the strength to offer to help at the shelter, in gratitude. Edith explains that her "young man" is taking her to a Clark Gable movie. McCoy surprises Edith by not knowing who Clark Gable is.
That evening, Kirk and Edith are strolling along on their date. As they make their way across the street, Edith mentions going to the Clark Gable movie. Kirk asks, "A what?" Edith responds in shock that Dr. McCoy said the same thing. Kirk, finally hearing of McCoy's presence, tells Edith to stay put and heads back to the shelter yelling for Spock. As he approaches the curb, McCoy exits the front door. With expressions of joy and relief, they hug.
Edith, confused by the commotion, begins to cross the street. A large truck is heading in her direction. Kirk, Spock, and McCoy look on to see the event that is about to take place. Kirk restrains McCoy and prevents him from rushing to Edith to save her life.
"Do you know what you just did?" McCoy questions. Kirk, in agony, pushes him away. Spock responds, "He knows, Doctor. He knows."
Having corrected history, the three men return through the portal to their own time; Scotty comments that they had left only a moment earlier. The Guardian offers more opportunities to visit the past, but Kirk declines, saying only "Let's get the hell out of here."
A heartbroken Kirk and the rest of the landing party return to the Enterprise. History has been saved, but at a terrible personal cost. As the party beams away, the howling of the wind once more becomes the only audible sound, as the Guardian awaits the next moment in time that it is asked a question.
"You! What planet is this?"
- - McCoy, startling a homeless man upon his arrival in the 20th century
- - McCoy, after an accidental injection of cordrazine
"Since before your sun burned hot in space and before your race was born, I have awaited a question."
- - Guardian of Forever, to Kirk
"Are you machine or being?"
"I am both and neither. I am my own beginning. My own ending."
- - Kirk and the Guardian of Forever
"All that you knew is gone."
- - Guardian of Forever, after McCoy changes the timeline
"My friend is obviously Chinese. I see you've noticed the ears. They're actually easy to explain."
- - Kirk to the police officer, explaining Spock
"A lie is a poor way to say hello."
- - Keeler, meeting Kirk and Spock
"I am endeavoring, ma'am, to construct a mnemonic memory circuit using stone knives and bearskins."
- - Spock, as Keeler sees his work on the tricorder
"Where would you estimate we belong, Miss Keeler?"
"You? At his side, as if you've always been there and always will."
- - Spock and Keeler
"Captain. Even when he doesn't say it, he does."
- - Keeler, on Spock
"Let me help. A hundred years or so from now, I believe, a famous novelist will write a classic using that theme. He'll recommend those three words even over I love you."
- - Kirk, to Keeler
"Peace was the way."
"She was right. But at the wrong time."
- - Kirk and Spock, on Keeler's peace movement
- - Keeler and McCoy
"Spock... I believe... I'm in love with Edith Keeler."
"Jim, Edith Keeler must die."
- - Kirk and Spock
"Save her – do as your heart tells you to do – and millions will die who did not die before."
- - Spock, to Kirk
"I could have saved her! Do you know what you just did?"
"He knows, Doctor...He knows."
- - McCoy (to Kirk) and Spock, on Keeler's death
"Time has resumed its shape. All is as it was before."
- - Guardian of Forever, after Kirk, Spock and McCoy return
"Let's get the hell out of here."
- - Kirk, before beaming back to the Enterprise
- Treatment is assigned, 16 March 1966
- Treatment by Cordwainer Bird, 21 March 1966
- Treatment by Harlan Ellison, 13 May 1966
- Teleplay by Harlan Ellison, 3 June 1966
- First draft: 13 June 1966
- Revised final draft by Harlan Ellison, 12 August 1966
- Second revised final draft: 1 December 1966
- Treatment, 29 December 1966
- First draft teleplay by Steven W. Carabatsos, January 1967
- Rewrite draft by Gene L. Coon, 9 January 1967
- Teleplay by Harlan Ellison, 23 January 1967
- Rewrite draft by D.C. Fontana, 23 January 1967
- Rewrite draft by Gene Roddenberry, 27 January 1967.
- It has been reported that there are two versions of this with one marked as the "Shooting Script" with a cover date of 27 January, but all of the other pages marked as 30 January.
- Final draft of rewrite: 1 February 1967
- Filmed: 3 February 1967 – 14 February 1967
- Score recording: 24 March 1967
- Premiere airdate: 6 April 1967
- First rerun: 31 August 1967
- Wins Hugo Award for Best Dramatic Presentation: 1968
- "Yesteryear", featuring the Guardian of Forever, premieres: 15 September 1973
- Six Science Fiction Plays, edited by Roger Elwood, includes the teleplay (albeit a slightly different version than Ellison published in 1995): 1976
- Star Trek Fotonovel #1: 1977
- Yesterday's Son, a novel featuring the Guardian of Forever: August 1983
- The City on the Edge of Forever limited edition hardcover: September 1993
- Entertainment Weekly ranks it as the #1 TOS episode: Fall 1994
- "Look Back in Anger", an essay by Harlan Ellison, appears in the TV Guide magazine special "Star Trek: Four Generations": Spring 1995
- Ranked #68 in TV Guide's 100 Most Memorable Moments in TV History: 1 July 1995
- The City on the Edge of Forever trade paperback: 1 July 1996
- Kirk and Spock action figures (Playmates Warp Factor series 5): 1998
- Remastered airdate: 7 October 2006
- The title of this episode refers to both the dead city on the time planet and New York itself, where the timeline will either be restored or disrupted. In Ellison's original script, Kirk, upon first seeing the city sparkling like a jewel on a high mountaintop, reverently says it looks like "a city on the edge of forever". In Ellison's first treatment for this episode, the city they traveled back in time to was Chicago.
- When asked in February 26, 1992 interview whether the makers of this episode consciously intended it to have the contemporaneous anti-Vietnam-war movement as subtext, associate producer Robert Justman replied, "Of course we did." 
- In The Star Trek Compendium, Allan Asherman suggests that the name "Keeler" is derived from the "keel" of a ship, the longitudinal element of a vessel that keeps it held together – much as Keeler herself keeps the time continuum from coming apart. It also could be interpreted as a hybrid of "killer" and "healer"--a reference to her dual role as the focal point of the time flow. In Ellison's first treatment for this episode, Edith's last name was Koestler.
- Ellison's original story outline and first draft script did not feature Dr. McCoy, but an Enterprise crewman named Beckwith, who was dealing drugs among the crew. Beckwith murdered a fellow crewman who was on the verge of turning him in, escaped to the planet the ship was orbiting, and went throught the Time Vortex, operated by a mysterious ancient race called "The Guardians" and changed history. The Enterprise was gone, and a savage pirate ship called the Condor in it's place full of renegade humans. Kirk and Spock follow Beckwith through the time portal to 1930 New York City, where Kirk falls in love with young social worker Edith Keeler (Koestler in the story outline). Finally, with the help of a legless World War I veteran called Rodent (who dies during the episode's action), they find Beckwith. In the end, Kirk does not stop him saving Edith: he freezes at the crucial moment and Spock prevents her rescue. (The Star Trek Compendium), 
- Ellison's script was unusable for the series for many different reasons. Gene Roddenberry objected against the fact that drug usage is still a problem in the 23rd century, and is even present among starship crews. Also, the production staff was heavily against Kirk's final inactivity. It seemed that being unable to decide and act, viewers could never be able to accept him as the strong leader figure in later episodes. Elements, such as the Guardians and the Condor and it's crew were simply impossible to create on the series' budget. (The Star Trek Compendium), 
- Originally then-story editor Steven W. Carabatsos got the job to rewrite Ellison's script, but his draft was not used. Instead, Ellison agreed to make a rewrite himself, which again, deemed unsuitable. Producer Gene L. Coon also got himself into the rewriting. Finally, the new story editor, D.C. Fontana got the assignment to rewrite Ellison's script and make it suitable for the series. Fontana's draft was then slightly rewritten by Roddenberry which became the final shooting draft. Much of the finished episode is the product of Fontana, who (as all the other writers) went uncredited for her contribution. Only two lines from Ellison's original teleplay survive in the final episode, both spoken by the Guardian: "Since before your sun burned hot in space, since before your race was born," and "Time has resumed its shape." (Inside Star Trek: The Real Story)
- Ellison was dismayed with the changes Roddenberry and Fontana made to his story, so much so, that he wished his credit to read "written by Cordwainer Bird", a request Roddenberry denied. Though Ellison had the final right to have his pseudonym attached, he claims that Roddenberry made veiled threats to the effect that if he did so he would "never work in this town again." Despite this feud, Roddenberry would list this as one of his top ten favorite episodes in an issue of TV Guide celebrating the 25th anniversary of Star Trek. In his own defense, Ellison stated he had no real problem with D.C. Fontana rewriting him, but rather with the extent and number of unpaid rewrites the studio and network got out of him, to say nothing of exaggeration-prone Gene Roddenberry telling fans that Ellison's script showed "Scotty selling drugs" (the script did not feature Scotty at all). (Star Trek: Four Generations)
- Roddenberry apparently denied Ellison's pseudonym request because he knew everyone in the science fiction community was aware that the "Cordwainer Bird" credit was Ellison's way of signaling his dissatisfaction with the way production people treated what he wrote. It would've meant that Star Trek was no different than all the other "science fiction" shows in mistreating quality writers, and could've resulted in prose science fiction writers avoiding contributing to the program. (Inside Star Trek: The Real Story)
- This was the most expensive episode produced during the first season, with a budget of $245,316, and also the most expensive episode of the entire series, except the two pilots. The average cost of a first season episode was around $190,000. Also, production went one and half days over schedule, resulting in eight shooting days instead of the usual six. (Inside Star Trek: The Real Story)
- There is a scene in the original 1960s broadcast version that has been partially deleted in some editions. When McCoy meets Rodent holding the milk bottle, the scene ends with McCoy collapsing, then cuts to McCoy meeting Keeler in the Mission. As originally filmed, after McCoy collapses, Rodent picks McCoy's pocket and takes his hand phaser (which he took from the transporter chief) and accidentally sets it on overload, and kills himself. The scene is present in its original form in DVD and laserdisc versions.  
- The network heavily objected againt Kirk's last line, "Let's get the hell out of here." and wanted it to be removed from the episode.
Sets and props
- The footage seen through the time portal is, for the most part, lifted from old Paramount films.
- The set used for New York City in this episode (called "40 Acres") is the same set used for The Andy Griffith Show. While Kirk is walking with Edith Keeler, they pass the courthouse and Floyd's barber shop. The same backlot was used for location shooting in "Miri" and "The Return of the Archons".
- The alley in which Kirk steals the clothing from the fire-escape is the same alley seen in "Miri", in which Spock and the guards have debris dumped on them by the children.
- Due to copyright issues, the original recording of Good Night, Sweetheart was replaced during the 1980s by another version for VHS and Laserdisc releases. Eventually this was corrected for the DVD release. New music was also composed for this episode, incorporating the song, but the composer of this music is not credited. 
- According to The Music of Star Trek, Fred Steiner takes credit for scoring new music (although sparse - only a few cues) for this episode. Most of the episode was tracked with prior music, including Joseph Mullendore, Gerald Fried and Alexander Courage. In the scene when the Rodent is stealing the milk, music from "Mudd's Women" is heard. An ominous, discordant piano note is added to the music to make it even more sinister. Also, music from "Shore Leave" is heavily present, including the score for the police chase, and some humorous cues in certain scenes. Most of the music accompanying the romance of Kirk and Edith Keeler are taken from "The Conscience of the King".
- Stock footage from "Dagger of the Mind" is used for Kirk's and Spock's reaction shots to McCoy's cordrazine overdose on the bridge.
- Double-exposures allowed Kirk and Spock to leap out of brick walls in this episode.
- During the speech scene in the Mission where Kirk and Spock have sat down with their soup, the director repeated (and slowed down) several close-up shots of Spock and Kirk, taken from later in the scene, and used them as reaction shots during Edith's prognostications.
- The close up of the tricorder showing the 'rewinding video' is used several other times throughout the series.
- The planet created for this episode is reused many times throughout the second and third seasons in two color corrected versions, tinted either blue or light-brown/sand.
- No stardate is logged in the episode. Bjo Trimble assigned a stardate of 3134 based on Harlan Ellison's original teleplay, which covered stardates 3134.6-8.
- A comparison of the calendar on the wall behind Kirk and Edith when she calls him a "common workman" to the real calendar from 1930 shows that this episode was taking place in May, 1930, however the calendar year and date were taped-over and the month also shows only 30 days.
- Clark Gable, who was by no means a leading man in 1930, was not the original choice of reference. The final shooting draft of this script has Edith reference "a Richard Dix movie", but the crew on the set felt Dix's name wouldn't be familiar to viewers in the 1960s.
- Edith Keeler tells Kirk "Let me help". Kirk replies, "A hundred years or so from now, a famous novelist will write a classic using that theme. He'll recommend those three words, even over 'I love you'." Kirk tells her that the novelist will come from a planet circling the far left star in Orion's belt: Zeta Orionis (or Alnitak).
- This is the first mention of Nazi Germany in Star Trek. A race which adopted a Nazi-style regime also appears in TOS: "Patterns of Force". The theme is reprised in later shows: on VOY: "The Killing Game", where Hirogen take over USS Voyager and use the holodeck to recreate Nazi Germany, and then in ENT: "Zero Hour", and "Storm Front", when agents from the Temporal Cold War send Captain Archer and the Enterprise NX-01 back to the Second World War. 
- The portal is revisited in the animated series episode "Yesteryear" and numerous books.
- In one scene in this episode, a poster can be seen advertising a boxing event at Madison Square Garden featuring "Kid McCook" vs. "Mike Mason". For the Star Trek: Deep Space Nine episode "Past Tense, Part II", scenic artists Doug Drexler and Michael Okuda created a near replica of this boxing poster for a scene set in 1930 San Francisco; the DS9 poster features the same boxers, and says that it is "their first rematch since Madison Square Garden".
- With regards to "The City on the Edge of Forever", Joan Collins has stated, "To this day, people still want to talk about that episode – some remember me for that more than anything else I've done. I am amazed at the enduring popularity of Star Trek and particularly of that episode." Collins adds, "At the time none of us would have predicted this know of longevity of the show. I couldn't be more pleased – or more honored – to be part of Star Trek history." (Star Trek 30 Years) Ms. Collins' memory of her Trek experience seems hazy, however. In her 1985 autobiography, Past Imperfect (p. 248) she makes a few errors regarding the episode: for example, in addition to the common mistake of referring to Mr. Spock as Dr. Spock, she identifies her character as Edith Cleaver instead of Edith Keeler, and she also claims that Spock, not Kirk, allowed her character to be killed – a plot point that was not in the version of the script that was actually shot. Most significantly, she claims Edith tried to "prove to the world that Hitler was a nice guy." Harlan Ellison objected to Collins' assessment, as that was not what the pacifist Edith ever tried to do. (citation needed • edit)
- This episode was chosen by William Shatner as his favorite episode of the entire series in the Star Trek: Fan Collective - Captain's Log DVD set. However, in his book Star Trek Memories, Shatner wrote that "The Devil in the Dark" was his favorite episode.
- This episode was chosen by Eugene W. "Rod" Roddenberry (Son of Gene Roddenberry) to be his favorite episode. 
- The book Star Trek 101, by Terry J. Erdmann and Paula M. Block, lists this episode as one of "Ten Essential Episodes" from the original Star Trek series.
- By popular acclaim, this is the single best episode of the original series, earning a 1968 Hugo Award for Best Dramatic Presentation (and the other four nominees were all episodes of Star Trek). It was 25 years before another television program received the honor, "The Inner Light". TV Guide also ranked it #68 in their 100 Most Memorable Moments in TV History feature in the 1 July 1995 edition, and also featured it in another issue on the 100 greatest TV episodes of all time.
- This episode is the only Star Trek episode to win a Writers Guild of America Award. Ellison took the award home for "Best Written Dramatic Episode", for his original version of the teleplay. On the award ceremony (where Roddenberry, Coon, Robert Justman, Herb Solow and other Star Trek production people were present), Ellison loudly spoke out against executives rewriting his and other writers' work in the industry. (Inside Star Trek: The Real Story)
Novelizations and adaptations
- Bantam Books published a series of novelizations called "fotonovels," which took photographic stills from actual episodes and arranged word balloons and text over them, to create a comic book formatted story. The first installment was an adaptation of this episode and featured a short interview with Ellison.
- In his adaptation of the story in Star Trek 2, James Blish explained to readers that he tried to preserve the best elements of both Ellison's original script and the final version. In the original, because Kirk does not act to prevent Edith's death, Spock later tells him that "No other woman was ever offered the universe for love." Blish's adaptation preserves the final version of Kirk allowing Edith to die, with the result that Spock tells him, "No other woman was ever almost offered the universe for love" – a far less poetic observation. Additionally, in this adaptation, during Edith's soup-kitchen prophecies, Spock leans over to Kirk and says, "Bonner the Stochastic," to which Kirk replies, "He won't be born for a hundred years yet." Bonner the Stochastic was a character who appeared in several of Blish's novels, and was inserted into this episode's prose adaptation by Blish himself. Stochastic refers to any process (including thinking) that uses randomness or conjecture. Fan fiction writers such as Claire Gabriel sometimes designate Bonner as the Orion novelist who came up with "Let me help". The final shooting script, dated 27 January 1967, specifies that the novelist's name is Patrick Koluuunahmeheheh Tajnaahme. Ellison's original screenplay, as well as Blish's adaptation, had an additional final scene, where Spock privately offers his condolences to a grieving Kirk and suggests that he accompany him to Vulcan to come to terms with the experience.
- The 2006 Crucible trilogy of novels follows up on plot elements from this episode. In "Provenance of Shadows" by David R. George III, it is shown what happened to the version of McCoy and Earth when he went back in time and altered history by saving Edith. McCoy places constant ads to try and signal for help in the future, but soon realizes that no help is coming. On advice, he makes his way south, ending up in a small town outside of Atlanta. There, he becomes the local doctor, marries a widow, and is eventually killed when the hostilities with the Nazis (spilling into US borders in this timeline) escalate.
- A sequel to this story was presented in Gold Key Comics' TOS issue #56 "No Time Like the Past".
- An episode of South Park, in which one of the children on a trapped school bus wearing a red commander uniform was killed, was given the same title as this episode.
"The City on the Edge of Forever" was the fifth episode of the remastered version of The Original Series to air. It premiered in syndication on the weekend of 7 October 2006 and featured new effects shots of the Enterprise and the time vortex planet from space, a slightly tweaked pan up from the planet's surface, an enhanced disintegration effect as Rodent accidentally sets off McCoy's phaser, cleaned-up mattes and static effects in the tricorder insert shots, and eliminated the freeze-framing over the end credits.
With regards to some of the new updates, Rossi stated, "For instance, in "City on the Edge of the Forever," there's a line where Captain Kirk says, "'These ruins extend to the distance.'" So we extended that shot into a 16:9 aspect ratio and created all these wonderful ruins." 
Not everything worked out as planned, however, "The Guardian planet [in 'City'] is this ancient world where supposedly the civilization died many millennia ago, and so I think what everyone expected to see is a gray, barren planet. Which we could have done – we can make a lot of gray, barren planets," says Rossi. In their attempted to recreate the consistency of the original soundstage-filmed planetside scenes, "We started looking at the backdrop – the cloth backdrop that they used – and it was kind of a purplish color, and so we wanted to tie these things together. What the visual effects team did was, create this rocky barren world with these giant purplish desert flats. Now, unfortunately, without us being able to come into your home and say, 'These are giant desert purplish flats,' I think a lot of people read them as oceans, which is kind of unfortunate. But that's what we were going for." 
- The next remastered episode to air was "I, Mudd".
Video and DVD releases
- US CED VideoDisc release: 22 March 1981.
- Original US Betamax release: 1985.
- US LaserDisc release: January 1986.
- US VHS release: 1986.
- UK VHS release (two-episode tapes, CIC Video): Volume 15, catalog number VHR 2311, release date unknown.
- Japan LaserDisc release: 10 November 1992.
- US VHS release: 15 April 1994.
- As part of the UK VHS Star Trek: The Original Series - Tricorder Pack collection: catalog number VHR 4373, 3 June 1996.
- UK re-release (three-episode tapes, CIC Video): Volume 1.10, 13 January 1997.
- Original US DVD release (single-disc): Volume 14, 11 July 2000.
- As a bonus on the Region 2 release of VOY Season 1 DVD
- As part of the TOS Season 1 DVD collection.
- As part of the Star Trek: Fan Collective - Time Travel DVD collection.
- As William Shatner's episode choice in the Star Trek: Fan Collective - Captain's Log DVD collection, featuring an introduction by Shatner and Joan Collins.
- As part of the TOS Season 1 HD DVD collection.
- As part of The Best of Star Trek: The Original Series DVD collection.
- As part of the TOS Season 1 Blu-ray collection.
Links and References
- John Harmon as the rodent
- Hal Baylor as a policeman
- David L. Ross as Galloway
- John Winston as the transporter chief
- Bartell La Rue as the Guardian voice
- William Blackburn as Hadley
- Howard Culver as the drunk
- Adolf Hitler as Adolf Hitler (voice)
- Carey Loftin as Truck driver
- Eddie Paskey as Leslie
- Unknown performersas
- Bobby Bass as stunt double for James Doohan
- Dave Perna as stunt double for DeForest Kelley
- Mary Statler as stunt double for Joan Collins
20th century; Alnitak; Bailey, Will; Barnes, Gus; Boise; constellations; cordrazine; duodynetic field core; Fischer's Infants Wear; flop; Floyd's Barber Shop; Gable, Clark; Germany; gold; Great Depression; Guardian of Forever; Kidd, Killer; Lloyd, Gus; Madison Square Garden; March Bake Shop; Mason, Mike; Mason, Ricky; McCook, Kid; missionary; mechanical rice picker; mnemonic memory circuit; Mulaney, Charley; needle; Orpheum; Outer Mongolia; platinum; Prado, Manuel; San Diego; Sencio, Buddy; silver; Singer's Book Store; suture; Star Dispatch, The; stone knives and bearskins; Thailand; Twenty-First Street Mission; Victor Ice Company; Walt's Restaurant; Widin Dairy Farm; World War II; zinc
- Harlan Ellison; The City on the Edge of Forever; White Wolf Publishing; ISBN 1565049640 (1st edition, hardcover, 1996)
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