History WhatCouldHaveBeen / StarTrek

** Intended as a continuation of [[Series/StarTrekTheOriginalSeries Star Trek: TOS]], but with an extensive visual update and new characters. The show got as far as being given an official transmission date in 1977, but was dropped when it was decided to produce a cinema film instead. The pilot of the series and the already partially-built sets were reworked into ''The Motion Picture'', while many of the remaining scripts got recycled ten years later as early [[Series/StarTrekTheNextGeneration TNG]] episodes.

** Intended as a continuation of [[Series/StarTrekTheOriginalSeries Star Trek: TOS]], but with an extensive visual update and new characters. The show got as far as being given an official transmission date in 1977, but dropped when it was decided to produce a cinema film instead. The pilot of the series and the already partially-built sets were reworked into ''The Motion Picture'', while many of the remaining scripts got recycled ten years later as early [[Series/StarTrekTheNextGeneration TNG]] episodes.

** Decker and Ilia were originally going to be regular characters on ''Phase II'', but instead ended up as one-off characters for ''The Motion Picture''. Persis Khambatta was actually cast to play Ilia for the series, but ending up playing her for the movie instead. Stephen Collins, however, was not cast as Decker until after the series had turned into a movie. Later on, Decker and Ilia were reworked as Riker and Troi for ''The Next Generation''.

* On the subject on spin-offs, there was apparently [[http://www.littlereview.com/getcritical/trektalk/darren.htm talks between CBS and James Darren for a Vic Fontaine show]] that would take place exclusively in the 60s. Darren was in but it's safe to say it didn't go anywhere.

* Back in the 90s there were steady rumors about a possible Captain Sulu and USS ''Excelsior'' show. ''[[Film/StarTrekVITheUndiscoveredCountry Star Trek VI]]'' and the [[Series/StarTrekVoyager VOY]] episode [[{{Recap/StarTrekVoyagerS3E2Flashback}} "Flashback"]] were a kind of backdoor pilot or popularity test for the idea, although there is no official word on that. The ''Excelsior'' was partially created as a possible replacement for the ''Enterprise'' for future movies.

[[AC:Series that never were]]

Do to length, this page has been organized by series.

* Jeffrey Hunter was originally cast in the role of Captain Christopher Pike that would later famously be replaced by Capt. James T. Kirk, played by Creator/WilliamShatner. Pike was meant to stay on as the series lead character, but Hunter was unavailable to film the second pilot. Rather than recast the role, they created a new character.
* When Hunter couldn't return but before Shatner signed on, the producers spoke to both Jack Lord and Lloyd Bridges about playing Kirk. Bridges immediately turned it down because he [[SciFiGhetto didn't like the thought of being on a sci-fi show]], but Lord was interested, provided they gave him way more creative control than they were comfortable with. Negotiations fell through and their third choice, Shatner, was selected.
* Spock's iconic Vulcan salute was actually [[ThrowItIn a last minute change]]. The original salute would have involved one Vulcan kneeling in front of another, while the standing Vulcan grabs the kneeling Vulcan's shoulders with both arms. Leonard Nimoy changed the salute because he felt it didn't fit the Vulcans' characterization, as they would have considered such physical contact a violation of privacy. Plus it just looked plain silly. Nimoy, being Jewish, adapted a traditional Jewish blessing to create the salute.
* The Klingon Koloth from the episode "The Trouble With Tribbles" was envisioned as a recurring character and arch-nemesis of Kirk's; this was established at their meeting at the beginning of the episode ("My dear Captain Kirk" / "My dear Captain Kololth"). William Campbell, the actor who played Koloth, once said in an interview that he would have played Koloth as [[EvilCounterpart Kirk's equal and opposite in the Klingon empire]], and someone who respected his adversary, to the point where he would save Kirk's life from other enemies on occasion, declaring that [[TheOnlyOneAllowedToDefeatYou nobody could kill Kirk but him.]] Unfortunately, Campbell was unavailable when Klingons were next cast, so we got Kang ("Day of the Dove") instead. When the character of Koloth reappears decades later in Deep Space 9 he remarks that his greatest regret is never getting to meet Kirk in battle.
* Creator/HarlanEllison[='s=] original script of "The City on the Edge of Forever", which was heavily rewritten, mostly due to cost. The aired version was almost entirely written by ''Star Trek'' story editor D. C. Fontana, who is uncredited. Ellison was not pleased, believing his version to be TrueArt. Notable differences include:
** Instead of [=McCoy=], history is changed by a random drug-dealing crew member. (Creator/GeneRoddenberry would later erroneously claim the script featured Scotty dealing drugs.) Unlike [=McCoy=], this character is a proper villain who murders a RedShirt who tries to report him. At the end of the episode, the drug-dealing crew member escapes into time again, only to be caught in a star the moment it goes supernova. Time replays itself continuously afterwards, forcing him to [[AndIMustScream relive the supernova again and again]] as his eternal punishment.
** Yeoman Rand is the only named character to beam down to the planet with Kirk and Spock. In the final episode, Scotty and Uhura share this role. (Rand had suffered from ChuckCunninghamSyndrome by the time the episode was filmed.)
** Instead of simply disappearing, the ''Enterprise'' is replaced by a ship of SpacePirates. This part was apparently forced on Ellison by ExecutiveMeddling, only to be deleted from the final version anyway. A similar concept was later used in the episode "Mirror, Mirror".
** The Guardians of Forever (note the plural) are nine-foot-tall aliens who guard the Time Vortex of the Ancients. Thus, the Guardian of Forever in the final episode is not just a CompositeCharacter of the two aliens, but also of the vortex itself.
** Kirk and Spock are taken in by a janitor and first encounter Edith Keeler when she makes her speech. Kirk and Spock recognize her as their focal point in time immediately and spy on her for awhile before making contact.
** Kirk does let Edith fall down the stairs, realizing in time that she is meant to die. Edith survives the fall, but is confused by Kirk's behavior and he ends up feeling guilty. When the climax rolls around, Kirk is unable to let her die and Spock has to step in to restore history. (This seems to be the change Ellison is most upset about, feeling that his version makes Kirk flawed and human instead of just TheHero.)
* In Roddenberry's pitch for the Original Series, Spock was described as "half-Martian" rather than half-Vulcan. Presumably, if this little detail had remained unchanged, a sentient Martian species would have become become part of the ''Trek'' verse. Spock was also originally planned to have red skin, but just before production started it was discovered that the makeup would make him look black on a black-and-white TV (which many people had at the time), and it was feared that this would cause controversy. As the later fallout involving Uhura's introduction showed, they were probably right.
* Roddenberry originally offered Creator/DeforestKelley the role of [[TheSpock Spock]]. He turned it down...obviously.
** If you think that's odd, imagine what could have been if Leonard Nimoy had decided not to return for the second season, which he seriously was considering. Had he opted out, producers were looking at an actor named Laurence Montaigne or ''Mark Lenard'' to replace him. Montaigne was later given the role of Spock's romantic rival, Stonn, while Lenard, who had already played the first Romulan on the series, would go on to his far more famous role, Spock's father, Sarek. Imagine that; Spock was almost his own father.
** There are rumors, denied by the actor himself, that when it seemed like Leonard Nimoy may not be available, Martin Landau was pursued by producers to play Spock, but he was signed to ''TV Series/MissionImpossible'' first.
* Several plans were made had ''Enterprise'' been renewed for another season, among them:
** An episode essentially nullifying the unpopular ending of "These Are the Voyages" and reviving [[spoiler: Trip]] in some way. (A book that was written, albeit without any guidance from the writers of the series, basically said that the death and its inclusion in the Holodeck program was part of a cover-up to hide the true purposes of a mission.)
** An episode called "The Treatment" that would have guest-starred the incredibly-long-lived ''Series/StarTrekTheNextGeneration'' character Guinan (Whoopi Goldberg) and would have had an appearance by Spock's grandfather, Skon, and the words (yes, there are words) of the original ''Series/{{Star Trek|The Original Series}}'' theme song being sung out loud by a Capellan (Chase Masterson). (Presumably without music...)
** [[https://www.youtube.com/watch?v=PjTN6apWiXk#t=41s Here's Tenacious D singing said Roddenberry lyrics live in concert.]]
* For that matter, what would have happened if the first ''[[Series/StarTrekTheOriginalSeries Star Trek: TOS]]'' pilot was the one that got picked up?
* [[http://www.ottens.co.uk/forgottentrek/phase2.php Star Trek: Phase II]]. Intended as a continuation of [[Series/StarTrekTheOriginalSeries Star Trek: TOS]] but with an extensive visual update and new characters. The pilot of the series and the already partially-built sets were reworked into ''The Motion Picture'', while many of the remaining scripts got recycled ten years later as [[Series/StarTrekTheNextGeneration TNG]] episodes.
** Decker and Ilia were originally going to be regular characters on ''Phase II'', but instead ended up as one-off characters for ''The Motion Picture''. Persis Khambatta was actually cast to play Ilia for the series, but ending up playing her for the movie instead. Stephen Collins, however, was not cast as Decker until after the series had turned into a movie. Later on, Decker and Ilia were reworked as Riker and Troi for ''The Next Generation''.
** When Nimoy refused to participate in the new series, Spock was replaced by Xon, a full-blooded Vulcan to be played by David Gautreaux. When Nimoy agreed to come back for the movie, Gautreaux was recast in a cameo role, as the commander of the space station which is destroyed by V'Ger. Later on, the character of Xon was reworked as the android Data for ''The Next Generation''.
* Joanna [=McCoy=], Dr. [=McCoy's=] daughter, who was in the UniverseBible for the original ''Trek'' series. In the third season, an episode was written which introduced her, but it eventually mutated into the infamous hippie episode "The Way To Eden" with Joanna replaced by Irina Galliulin. Joanna was then set to appear in the fourth season, but the show got cancelled first. She was finally mentioned (but unseen) in ''WesternAnimation/StarTrekTheAnimatedSeries'' and, of course, she has made many appearances in the ''Franchise/StarTrekExpandedUniverse''. But technically she still does not canonically exist.
** By the way, the "Michael Richards" who has co-story credit isn't ''that'' [[Series/{{Seinfeld}} Michael Richards]] but a pseudonym for D.C. Fontana, who wrote the original script for "Joanna" (the episode's initial title); she washed her hands of it after rewriting took effect.
* A number of ''Trek'' alumni have attempted to create a new series. One such example was by Jonathan Frakes, who attempted to pitch a series, going by his comments, focusing on the now-Captain Riker of the U.S.S. ''Titan'', alluded to during ''Film/StarTrekNemesis''. Paramount execs vetoed it to prevent "franchise fatigue", which Frakes agreed made sense.
* In the original plans for the series the warp drive didn't counteract TimeDilation. (Which may be why we never saw present-day Earth in the series). This is where the concept of stardates originally came from; which shows that the creators didn't fully understand the concept: special relativity means there is no universal time!

** The original concept for Enterprise as conceived by Rick Berman and Brannon Braga was to have the first season take place on Earth while the NX-01 Enterprise was being constructed, centered around a plot and setting inspired by the film ''Film/TheRightStuff''. The season would have established and fleshed out the main characters as well as demonstrate how difficult the project was for the newly United Earth and recently commissioned Starfleet, all the while having the characters have to bypass controversy and fear over the mission being flared up by a rapidly xenophobic faction on Earth who wanted to stop the mission (an aspect that was revived for the final season). The executives at UPN would have nothing of this, as it was too much of a departure from the typical Trek formula, and being that the last time a Trek series deviated from the norm (Deep Space Nine) it performed weakly in comparison to the other series. As such, they didn't want to deviate too much from the standard setup, hence why the first two seasons are very similar to what had already been seen and done on The Next Generation and Voyager. The second season episode "First Flight" is a capsule of this rejected idea.
** The Klingon crash landing in Oklahoma in the pilot was originally supposed to be a Klingon attack on Earth (specifically Iowa) that would force the NX-01 to launch and find and fight the Klingons. This also probably served as the inspiration for the Xindi attack on Earth and subsequent story arc that started with "The Expanse".
** Another aspect axed by executives was the NX-01 mission being portrayed as incredibly dangerous and risky, with crew members regularly dying and the trauma of this making the characters wonder if it's all worth it. This was seen as too dark and dangerous, hence why the first two seasons are safe even when compared to the safest of TNG and Voyager. After season two, the show gets more dangerous perhaps due to less executive meddling.
** The Temporal Cold War plotline, often considered one of the worst aspects of the show, was an executive idea forced on the series out of a desire to connect it more to the TNG era to get more viewers. It ironically had the opposite effect, driving away many would-be fans which is why the plotline was totally canned the minute executives were no longer paying attention.
** The Suliban were conceived as a not-so-subtle reference to the "Taliban" and terrorism in general only after executives killed the idea of making the Klingons the main villains, which would have suited the prequel setting far more. The Xindi in turn were conceived of after the failure of the Suliban to interest viewers and only after the Klingons (and later the Romulans) were again rejected as villains for season three.
** Writer David A. Goodman pitched the idea of a human spy being planted on Vulcan in the early days after First Contact, to see if the Vulcans were actually hostile invaders, but it never got off the ground. Years later, he'd feature a story similar to this in the reference book he wrote "Star Trek: Federation The First 150 Years".
** An episode called "Kilkenny Cats", which would have featured the Kzinti, the ''Star Trek'' version of the Cat-like race of the same name that is seen in Creator/LarryNiven's ''Literature/KnownSpace''.
** Shran would have become a member of the crew. No doubt foreshadowing Andoria's co-founding of the Federation with Vulcan, Earth, and Tellar.
** Interestingly enough, Shran's actor, Creator/JeffreyCombs, had auditioned years previously for the role of Riker on The Next Generation.
** Several episodes that would explain or foreshadow events in the "future" ''Star Trek'' Series (mainly TOS): Stratos, NOMAD, Flint, The Borg Queen, "This Side of Paradise" and possibly more on the Mirror Universe would have been explored.
** Creator/WilliamShatner may have finally showed up... as an aged MirrorUniverse James T. Kirk who had been shunted through time and space!
** And, believe it or not, there might have been a televised crossover with ''Series/DoctorWho''. Seriously. Creator/RussellTDavies was planning on making overtures to Paramount for a story in which the TARDIS showed up on the [[Series/StarTrekEnterprise NX-01]], but the Trek series was canceled before he could do so. He admitted it probably wouldn't have happened (for obvious reasons), and certainly not in a way that the two creative teams would have liked. But still, the two longest-running SF Franchises in history...
** [[http://www.bleedingcool.com/2012/02/10/scoop-doctor-who-star-trek-official-crossover/ I have a Number One now. Number Ones are cool]]

* When the character of Janeway was being developed, the producers weren't sure if they were really going ahead with the first female ''Trek'' lead, and spoke to British actor Nigel Havers about the role, as well, as ''Film/AlienNation'' actor Gary Graham (who also claims to have read for the role of Sisko). For that matter, Janeway was the first regular ''Trek'' role to actually be recast before the series aired. Initially Oscar-nominated actress Genevieve Bujold was cast as Captain ''Nicole'' Janeway. After she departed, the character's name became Elizabeth Janeway and only became Kathryn when Kate Mulgrew was finally cast and the name seemed to suit her better.
* Tuvok was initially developed as an older Vulcan, with an actor in his 50's or even early 60's playing him. None of the actors in that age range satisfied producers, and so instead, Tim Russ became ''Trek'''s first black Vulcan. They kept the idea of Tuvok being well over 100, however.
* Creator/RobertPicardo desperately wanted to be cast on ''Voyager'', but as ''Neelix'', whom Picardo was convinced would become the show's breakout character. Thankfully he was persuaded to take the "boring" role of the Doctor, turning that role into the breakout character instead.
* Tom Paris on ''Series/StarTrekVoyager'' was originally meant to be one-off TNG character Nicholas Locarno (who was played by the same actor and had roughly the same past); reasons for changing it include royalties and the far more likely idea that, unlike Tom, Nicholas was "irredeemable".
** For that matter, even before the Locarno idea, the producers yet again wanted this character to be Ro Laren, which would have made sense as she was now Maquis. Again, however, Michelle Forbes turned the opportunity down, and the writers started thinking about what other "fallen" characters could be used, and came up with Locarno, who eventually became Paris.
** Additionally, the Year of Hell was not originally just a two-parter but instead the plan for the entire fourth season, until ExecutiveMeddling ended that.
** Only if the season finale wasn't a massive ResetButton [[spoiler:like the two-part episode's ending was]], which would have reduced a grim and gritty season to a ''Series/{{Dallas}}'' cop-out.
** It was, indeed, foreshadowed in the season three episode "Before and After", where Kes' time-jumps were caused by a Krenim temporal weapon in Voyager's future, although Kes would leave shortly into the fourth season.
** In said foreshadowing, it showed a version where Janeway and Torres were killed off, leaving Chakotay in command of the ship. It also had Neelix as a security officer, and probably would have had some interesting plots later on.

* The producers of ''Series/StarTrekDeepSpaceNine'' briefly considered setting the series on Bajor itself, within a planet-based facility, with heavy use of location filming for the exteriors of the base. Though hardly a huge change to the format of the eventual series, it would have opened up storytelling possibilities, with some Bajorans suspecting that they'd simply traded one set of occupiers for another (an idea that nevertheless made it into the series, at least as subtext).
** At first it wasn't certain that the captain on this show would be black, and Richard Dean Anderson was considered as the lead. Later, when they decided that the character would be black, James Earl Jones and Carl Weathers were both approached. Had Jones been cast, the character would have been an admiral and Jake would have been his ''grand''son, but eventually it was agreed that a younger lead was a better plan.
** Melora from "Melora" was meant to be the station's chief science officer, but this proved impossible due to problems with portraying zero gravity. It was possible, however, to feature her as a one-off character. The change is for the better -- what with [[FridgeLogic people already being annoyed at a character from a low gravity planet being inexplicably humanoid]]. In the novel 'verse, she would eventually become head of stellar cartography on the ''[[Literature/StarTrekTitan Titan]]''.
** The role of Major Kira was initially intended to be ''Next Generation'' recurrer Ro Laren, which was the entire reason for setting the show near Bajor. When Michelle Forbes declined to do a series, Nana Visitor was hired instead. Although the show would certainly have been well-done, showrunners claim that having Kira -- who was quite emphatically ''not'' a member of Starfleet, and didn't much like the Federation -- opened up possibilities for internal conflict that would not have otherwise existed.
** "Homefront" and "Paradise Lost" were going to be the finale of season 3 and the premiere of season 4 respectively. However, Paramount decided to boost ratings by introducing a Klingon storyline and adding a TNG regular (they decided on Worf) to the main cast.
** The series was originally conceived with The Borg as the primary antagonist in mind. The idea was dumped because it was felt The Borg were too powerful for the main characters to thwart week after week which is the reason they rarely appeared in TNG. They then considered the Romulans and Klingons (an idea they did partially explore midway through the series) but eventually settled on the Cardassians and later a new race, The Dominion. Their appearance in the pilot is all that is left of this idea.
** The Dominion was originally going to be a counterpart of The Federation, as an alliance of many different races, just bent on conquest and domination instead of exploration and understanding, with no clear one as the "master race". It was axed due to the pains of both consistently writing and introducing new alien races and the budget pains of having to portray them week after week, and eventually just became three races, one of which is clearly in charge. Despite this, different member races did make appearances here and there.
** Creator/LeonardNimoy expressed interest in playing Mirror Universe Spock in an episode.
** Ronald Moore originally wanted to name the Defiant ''Valiant'', but this was rejected out of fear people would confuse it with Voyager. The name Valiant was eventually used for one of the Defiant's sister ships.
*** The episode that featured said ship, "Valiant", it was supposed to be Jake and Kira boarding the ship. However, the writers realized that would be a mistake - Kira would have kicked all of the cadets' asses and hauled the ''Valiant'' right back into Federation space. Thus, Kira was replaced with Nog.
** Initially it was Vulcan, not Betazed that was conquered by the Dominion during ''In the Pale Moonlight'', but the writers nixed that because they felt it would offer Sisko too much justification for the extreme measures he then undertook.

* ''Series/StarTrekTheNextGeneration'': The original concept for Sela is that she would have been Tasha and Castillo's daughter, raised by Romulans, and eventually have a HeelFaceTurn.
** The very earliest concept for the series seen it as being set more than a century after the original, featuring the NCC-1701-7 (not a typo, they really were going to have a number instead of a letter), and with the ship being crewed by... cadets. When Creator/GeneRoddenberry heard about these plans, which were put forward by the studio executives completely independently of him, he rang them up and insisted on taking personal charge of the series.
** [[CreatorsPet Wesley]] was also, originally, going to be a teenage girl, ''Lesley'' Crusher, until Roddenberry decided to cast Creator/WilWheaton in the part, and gave the character his own middle name.
** Wes was also originally intended to be the product of an affair between Picard and Beverly Crusher. This was alluded to in early seasons, but wound up going nowhere.
** At one point in development, it was considered to ditch the starship concept altogether and instead increase the power of the transporter to allow the crew to beam from planet to planet every week. The idea didn't last very long, [[Franchise/StargateVerse though it did crop up elsewhere]].
** The Borg were at one point supposed to have a much bigger part in the series than they did. Those Romulan and Federation outposts that were wiped out at the end of the first season were supposed to be foreshadows of a major Borg invasion of the Romulan Empire. A writer's strike wound up forcing the producers to cut and change the story to what was seen in "The Best of Both Worlds". Certainly would have been a darker turn for the series though.
** The Borg were originally supposed to be an insectoid race, related to the invading parasites from the first-season episode "Conspiracy". They were later reimagined into more budget-friendly humanoid cyborgs.
** Other early ideas for TNG included the Neural Parasites from "Conspiracy' being later linked to the (originally insectoid, not cybernetic) Borg Hive. The parasites would have been the Borg vanguard of advanced scouts. The 1st season would have ended with a joint investigative mission into Borg activity by the Romulans and the Federation, chronicled by a trilogy of episodes which would have formally introduced the Borg. Due to the Writer's Strike, these plans were abandoned although elements were present in filmed episodes; however, the neural parasites' connection to the Borg never became canon and was dropped, with the parasites not making another appearance and the Borg reimagined as cybernetic humanoids instead of an insectoid hive.
** Take a look [[http://www.lettersofnote.com/2010/08/star-trekcasting.html at this casting letter]] for a bunch of What Might Have Been. [[Series/ThePretender Patrick Bauchau]] as Picard? Creator/WesleySnipes as Geordi? Creator/JennyAgutter as Beverly? Rosalind Chao as Tasha? ''Series/FunHouse'' host J.D. Roth as Wesley?
** Take another look at that casting letter. Notice a name missing? That's right, Worf was not initially a planned part of the series. The producers toyed with the idea of a Klingon as a regular crew member in order to parallel the repaired relations between the USA and Russia. The idea for Worf was actually rather last-minute, which is reflected in early cast promotional photos that he is absent from. It also explains why his character didn't really seem to have a permanent post in the first season. One wonders what would have happened if Denise Crosby had not left.
** Data had a remarkably different original backstory as a product of alien biomechanics. This idea was probably still in the writers' minds as of TNG "The Naked Now" when Data compared himself to a biological life form in an attempt to explain to Picard how it was that he could get intoxicated by the virus in that episode.
*** Creator/PeterDavid took that part and ran with it in ''Q-Squared'' where an alternate timeline sees Data built as a "human-oid": A positronic brain in a human body.
*** Early ideas for Star Trek: The Next Generation, from episode treatments and scripts that were ultimately not filmed, and from various early versions of episode storylines, include a very different origin for the character of Lt. Cmmdr. Data. Before the episode "Datalore" as filmed established that Data was a closely human android built by Dr. Soong, a human, his original backstory, according to the unfilmed episode "Terminus" and early versions of "Datalore," was very different: Data had been created by an alien species whose technology the Enterprise would encounter but who would remain mostly mysterious and unseen. The aliens (in some versions of this origin story they were a civilization of machines) constructed Data to resmemble humans, whom they admired and tried to preserve whenever they encountered them. He was meant to serve as a repository of the memories of a colony of humans that the aliens/androids had found were being killed by an alien force (eventually developed into the Crystalline Entity). The aliens/androids regretted not being able to save the humans so they constructed Data in human form to save the colonists' memories and knowledge. In other variations of the early "Datalore" story concept, the character that became Data's "brother" Lore started as a female android named "Minuet" before evolving into Data's "evil twin." "Minuet" eventually did show up in the series, but as a holographic love interest for Riker (who was to fall in love with Minuet during a rescue mission) before Minuet was rewritten as a gynoid love interest for Data, before they decided to go with an "evil twin" instead. Data's "evil twin" was an idea itself borrowed from "Terminus," a separate episode concept with some similarities to later, early versions of "Datalore." Also, the Crystalline Entity was initially written as "luring" humans inside and draining them of their neural energy before it was rewritten as a space-dwelling creature that fed by converting mass to energy and stripping entire planets of their ecosystems. In another draft there was no Crystalline Entity seen, "something" was implied to have killed the colonists. In another draft, and in "Terminus," alien (robot/android-operated or auomated) spacecraft or "objects" that can terraform planets for human life and create Data-like androids, played similar mysterious aggressor/object-of-curiosity plot roles.
** Elements of an unfilmed TNG story called "The Neutral Zone" (unrelated to the filmed episode of the same name), specifically the Enterprise carrying a wheelchair-bound Star Fleet dignitary on a critical mission, made it into the filmed episode "Too Short A Season." The "Neutral Zone' character, Commander Billings, the wheelchair bound dignitary, was a Star Fleet security officer who had originally rescued Tasha Yar from her hellish failed colony planet. The Enterprise would have carried Billings on a mission to open trade relations with the Romulan Star Empire. Billings was rewritten as the elderly Admiral Mark Jameson and instead of a Romulan trade mission, the Enterprise carried him to a wartorn planet for a hostage negotation. Instead of Dr. Crusher performing an experimental procedure which involved transplanting Data's spinal fluid in to Billings so Billings could walk again, as in "The Neutral Zone," Admiral Jameson instead came aboard with the mysterious de-aging compound he'd obtained from another planet in "Too Short A Season." The arms deal angle was similar to Kirk's solution to the Klingon interference with social development on the planet in a TOS episode, "A Private Little War," and there are unconfirmed rumors that this characters and this situation were based on Kirk and the Hill People or were originally about Kirk and the Hill People, but this has never been officially confirmed.
** Another episode, "Blood and Fire," would have been an AIDS allegory, with Regulan bloodworm infections being one stage in an invasive alien parasites' life cycle. There are many versions of the story of why this particular episode was never filmed. David Gerrold had originally written two (very, very subtly) gay characters into the story, and was later pressured to remove these characters, and the script was rewritten several times (eventually it became a story about zombie infection) before it was dropped, even after the reference to the two gay characters had been removed several drafts ago.
** Several episodes that also were unfilmed in the 1st and 2nd seasons as well as several early versions of 1st Season episodes featured the Ferengi either in person or referenced as a much greater threat to the Federation than they actually were as filmed and in canon; the Ferengi were originally supposed to be an aggressive, expansionist empire out there making deals with the Federation's enemies, and they were meant to be terrifying. References in several episodes would have built up their threat, and appearances in other episodes would have depicted them as warriors who were in a state of "cold war" or even "undeclared war" with the Federation and often competed directly with the Enterprise crew in a role similar to the Klingons in the Original Series. However, with the Ferengi debuting ridiculously and being later retooled as a species of high-tech merchants who could provide comic relief, instead of super-aggressive exploiters with heavy warships, the Romulans gradually assumed the role of the series' main antagonists.
** Gene Roddenberry originally wanted no aliens from TOS to appear on TNG, and only relented when it was suggested that Worf's presence on the bridge could open up storytelling possibilities now that the Federation and the Klingons had made peace (early idea in TNG was the Klingons actually joined the Federation; later retconned). Another unfilmed early episode featured a Romulan crewmember on the Enterprise too, suggesting/implying that the Romulans had "joined" the Federation like the Klingons. See below.
** Early TNG made several references to an early concept that the Klingons "joining" the Federation. Later TNG and DS 9 retconned this as being an alliance (the Khitomer Accords, as depicted in Star Trek VI), not UFP membership.
** The sixth season episode "Second Chances" deals with Riker dealing with a copy of himself created 8 years prior. An idea considered at the time was to have the original Riker accidentally die during the episode and then have 'Lt. Riker' join the crew, taking Data's position at OPS while Data became the new first officer.
** Interestingly, there is an early model of the Ambassador Class visible in the conference room as a mural of all the Starfleet ships named Enterprise. The final Ambassador design was very different, but the ship in the mural was never changed. Other examples may be present in the various models of ships found on desks of officers; leftovers of models that were going to be used but never were.
** The character that eventually became Worf was originally supposed to have been a Marine from the Klingon Empire who simply held a post on a Federation ship.
** Originally, the crew was supposed to keep the original colors from TOS - Yellow for Tactical, Red for Engineering and Blue for Medical. However, having seen Frakes and Stewart in the red uniforms, they thought they looked better in them and flipped the Tactical and Engineering colors. This is later referenced in the ''Deep Space Nine'' episode "Trials and Tribble-ations" when Sisko puts on the wrong colored uniform and has to be reminded of the old ways.
** The episode "The Outcast" involved a planet of aliens with only one gender, but were all played by women. Recognizing the UnfortunateImplications, Jonathan Frakes fought hard to have his love interest for the episode be played by a man, but was ultimately unsuccessful.
** The Ferengi were originally planned as the recurring villains of ''The Next Generation'', filling the role which the Klingons had played in the original series. In "The Last Outpost", the first episode featuring the Ferengi, they are heralded with all the fanfare of real serious villains. It turned out no one could take the Ferengi seriously as villains and subsequent episodes gradually reduced them to comic relief. Later on, the Borg were created the fill of the role of recurring villain species.
*** And when the Borg proved to be too much of an EldritchAbomination to write convincing stories about (priot to their VillainDecay on ''Voyager'', anyway), the writers tried a ''third'' time, and came up with the Cardassians, a frightening villain (used to great effect on ''Deep Space Nine'' as well) that nonetheless could be defeated.

** Creator/PeterDavid took that part and ran with it in ''Q-Squared'' where an alternate timeline sees Data built as a "human-oid": A positronic brain in a human body.

* Spock's iconic Vulcan salute was actually [[ThrowItIn a last minute change]]. The original salute would have involved one Vulcan kneeling in front of another, while the standing Vulcan grabs the kneeling Vulcan's shoulders with both arms. Leonard Nimoy changed the salute because he felt it didn't fit the Vulcans' characterization, as they would have considered such physical contact a violation of privacy. Plus it just looked plain silly.

** Take a look [[http://www.lettersofnote.com/2010/08/star-trekcasting.html at this casting letter]] for a bunch of What Might Have Been. [[Series/ThePretender Patrick Bauchau]] as Picard? Wesley Snipes as Geordi? Creator/JennyAgutter as Beverly? Rosalind Chao as Tasha? ''Series/FunHouse'' host J.D. Roth as Wesley?

** Leonard Nimoy expressed interest in playing Mirror Universe Spock in an episode.

* Robert Picardo desperately wanted to be cast on ''Voyager'', but as ''Neelix'', whom Picardo was convinced would become the show's breakout character. Thankfully he was persuaded to take the "boring" role of the Doctor, turning that role into the breakout character instead.

** The Ferengi were originally planned as the recurring villains of ''The Next Generation'', filling the role which the Klingons had played in the original series. In "The Last Outpost", the first episode featuring the Ferengi, they are heralded with all the fanfare of real serious villains. It turned out no one could take them seriously as villains and subsequent episodes gradually reduced them to comic relief. Later on, the Borg were created the fill of the role of recurring villain species.

** The Ferengi were originally planned as the recurring villains of ''The Next Generation'', filling the role which the Klingons had played in the original series. In "The Last Outpost", the first episode featuring the Ferengi, they are heralded with all the fanfare of real serious villains. It turned out no one could take them seriously and subsequent episodes gradually reduced them to comic relief. Later on, the Borg were created the fill of the role of recurring villain species.

** When Nimoy refused to participate in the new series, Spock was replaced by Xon, a full-blooded Vulcan to be played by David Gautreaux. When Nimoy agreed to come back for the movie, David Gautreaux was recast as the commander of the space station which is destroyed by V'Ger. Later on, the character of Xon was reworked as the android Data for ''The Next Generation''.

* [[http://www.ottens.co.uk/forgottentrek/phase2.php Star Trek: Phase II]]. Intended as a continuation of [[Series/StarTrekTheOriginalSeries Star Trek: TOS]] but with an extensive visual update and new characters. The pilot of the series and the already partially-built sets were reworked into [[TheMovie The Motion Picture]], while many of the remaining scripts got recycled ten years later as [[Series/StarTrekTheNextGeneration TNG]] episodes.

* The Klingon Koloth from the episode "The Trouble With Tribbles" was envisioned as a recurring character and arch-nemesis of Kirk's; this was established at their meeting at the beginning of the episode ("My dear Captain Kirk" / "My dear Captain Kololth"). William Campbell, the actor who played Koloth, once said in an interview that he would have played Koloth as [[EvilCounterpart Kirk's equal and opposite in the Klingon empire]], and someone who respected his adversary, to the point where he would save Kirk's life from other enemies on occasion, declaring that [[TheOnlyOneAllowedToDefeatYou nobody could kill Kirk but him.]] Unfortunately, Campbell was unavailable when Klingons were cast in subsequent shows, so we got Kang ("Day of the Dove") and Kor ("Errand of Mercy") instead. When the character of Koloth reappears decades later in Deep Space 9 he remarks that his greatest regret is never getting to meet Kirk in battle.

** The original concept for Enterprise as conceived by Rick Berman and Brannon Braga was to have the first season take place on Earth while the NX-01 Enterprise was being constructed, centered around a plot and setting inspired by the film"The Right Stuff". The season would have established and fleshed out the main characters as well as demonstrate how difficult the project was for the newly United Earth and recently commissioned Starfleet, all the while having the characters have to bypass controversy and fear over the mission being flared up by a rapidly xenophobic faction on Earth who wanted to stop the mission (an aspect that was revived for the final season). The executives at UPN would have nothing of this, as it was too much of a departure from the typical Trek formula, and being that the last time a Trek series deviated from the norm (Deep Space Nine) it performed weakly in comparison to the other series. As such, they didn't want to deviate too much from the standard setup, hence why the first two seasons are very similar to what had already been seen and done on The Next Generation and Voyager. The second season episode "First Flight" is a capsule of this rejected idea.

** Take a look [[http://www.lettersofnote.com/2010/08/star-trekcasting.html at this casting letter]] for a bunch of What Might Have Been. [[Series/ThePretender Patrick Bauchau]] as Picard? Wesley Snipes as Geordi? [[Film/AnAmericanWerewolfInLondon Jenny]] [[Creator/JennyAgutter Agutter]] as Beverly? Rosalind Chao as Tasha? ''Series/FunHouse'' host J.D. Roth as Wesley?

** The Temporal Cold War subplot was a fully executive decision due to Paramount's desire to make Enterprise both a prequel and a sequel, out of fear that the series being a true prequel would not be popular with fans. Ironically viewers hated the concept and it is a major contributor to the negative reception the show garners among fans to this day. The original writers and producers for the show claim to regret even having to write it, claiming it was "strangulating" to what they really want to do with the show (they never planned to have any time travel stories in fact). Season four lost most of the executive meddling and gained new producers and writers interested in exploring the prequel concept, so that's why the TCW is totally ditched in the beginning of the season without much of a conclusion and the series finally got to be the prequel it was originally supposed to be all along. Brannon Braga later admitted that the approach season four took was what he and the other writers originally had in mind for Enterprise, story arcs that explain the history of the Star Trek universe, the beginnings of Earth's conflict with Romulus and the formation of the Federation. As such, many fans tend to agree that season four is either the best of the series or the only season even worth watching.

* The original concept for Enterprise was for either most of or the entire first season to take place on Earth, with Captain Archer assembling a crew while the Enterprise is being constructed, and the season would explore the massive difficulties for the newly United Earth and the newly charted Starfleet in undertaking this project, and the opposition among many humans to the project, including a racist, xenophobic group afraid that the mission will reveal Earth's location to thousands of hostile species. Executive meddling forced the writers to axe this entire idea for being too risky a departure from the Trek format and they forced the Enterprise to launch in the very first episode. The second season episode "First Flight" gives a glimspe of what the first season was originally envisioned to be. The only aspect of this original concept to survive was the idea of xenophobic human terrorists (featured in the series' last two parter) which is ironic given this could be considered the most radical departure from the traditional Trek formula, which tends to portray the humans of the future as being above prejudice and hatred.
** The Klingon crash landing in Oklahoma was originally going to be a Klingon strike force attacking Iowa, which would lead to the NX-01 being launched in an urgent mission to find out and combat the Klingons, and further the anxiety and opposition among many humans afraid of hostile aliens reaching Earth. This story arc would have served as an explanation for Picards infamnous line about the disastrous first contact between Klingons and Humans.
** After Enterprise got into space, the writers envisioned space being viewed as very dangerous and hazardous, as this was humanity's first long term deep space mission, and starting what Kirk, Picard, etc. take for granted in later centuries. The common Trek tech like phasers and transporters, etc. would be gradually introduced throughout the series, making each season a bit safer. The executives felt this also was too risky and less traditional, so the first two seasons largely portrayed the NX-01 mission as safe as the Enterprise-D's mission in The Next Generation, which takes place 200 years later, loaded with more or less the same technology we've seen in the rest of the franchise. This is also ironic given many fans were angry that this prequel series did not portray space as more dangerous and often didn't feel like a prequel due to this and other reasons, but the idea of space being dangerous for the crew was what the writers intended all along, it was executive meddling that stopped it. They did eventually get to explore the idea of making space more dangerous in seasons 3 and 4, due to less executive meddling.
** The series originally was going to explore more thoroughly how Earth became the near paradise seen in Trek, how Earth united after first contact with the Vulcans, and the various interstellar space programs that preceded Starfleet. Yet again, this was axed by executives who felt fans would be bored with explanations of the universe and not just typical alien of the week episodes.

** Alien baddies the Suliban were an executive idea as well, as the series was originally going to feature the Romulans and Klingons as the prominent threats to Earth. The Xindi were thought up by the writers after executives continuously axed the idea of the Romulans being the main villain (for whatever reason). Season four changed that by dumping the Temporal Cold War altogether and finally making the Romulans and Klingons the main baddies. The Earth-Romulan War was finally going to be seen by season five according to series producer Manny Coto, but the cancellation of course ended that.

** Ronald Moore originally wanted to name the Defiant ''Valiant'', but this was rejected out of fear people would [[ViewersAreMorons confuse it with Voyager]]. The name Valiant was eventually used for one of the Defiant's sister ships.