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[[caption-width-right:350: [[SugarWiki/AwesomeMusic Taa-ta-ta-ta-ta-ta-taaaaaa!]]]]

->''"If my calculations are correct, when this baby hits 88 miles per hour, you're gonna see some serious shit."''
-->-- '''Dr. Emmett L. "Doc" Brown'''

An extraordinarily successful 1980s trilogy of TimeTravel {{movies}} starring Creator/MichaelJFox and Creator/ChristopherLloyd (with an [[WesternAnimation/BackToTheFuture animated]] SpinOff series) which has received several {{homage}}s. They combined FishOutOfWater comedy with high-stakes drama, making deft use of threatened TemporalParadox.

The films are notable for their running gags, based on [[IronicEcho similar events occurring across time]], and solidified the career of Creator/RobertZemeckis (who went on to make ''Film/WhoFramedRogerRabbit'', ''Film/ForrestGump'', ''Film/{{Beowulf}}'' and ''Film/AChristmasCarol2009'' to name a few). The series itself is very successful beyond the films, later spawning [[WesternAnimation/BackToTheFuture a cartoon]], a Ride/UniversalStudios ride[[note]](Later replaced by a ride based on ''WesternAnimation/TheSimpsons''.)[[/note]], [[VideoGame/BackToTheFuture a video game]] (or [[VideoGame/BackToTheFuture1989 two]]), [[Pinball/BackToTheFuture a pinball game]], [[TabletopGame/BackToTheFuture a card game]], a cinematic re-release in 2010 (to celebrate the 25th anniversary), once again in 2015[[note]]In the second movie, Marty goes to October 21st, 2015.[[/note]], an {{interquel}} comic book series from Creator/IDWPublishing, and several spinoff products.

The franchise includes:

[[index]]
* ''Film/BackToTheFuture'', the first film.
** ''Film/BackToTheFuturePartII''
** ''Film/BackToTheFuturePartIII''
** [[Literature/BackToTheFuture George Gipe's novelization of the first film]][[note]]done ''before'' it was released[[/note]], which ''Literature/BToTheFTheNovelizationOfTheFeatureFilm'' dissected.
** ''Script/NumberTwo'', the first draft of ''Back to the Future: Part II''.
* ''Ride/BackToTheFutureTheRide'', the simulator ride based on the films.
* ''WesternAnimation/BackToTheFuture'', the AnimatedAdaptation.
* ''Pinball/BackToTheFuture'', the arcade {{Pinball}} machine based on the films.
* ''TabletopGame/BackToTheFuture'', the Looney Labs card game based on the films.
* ''[[VideoGame/BackToTheFuture1989 Back To The Future]]'', the 1989 video game for the UsefulNotes/NintendoEntertainmentSystem based on the first film.
* ''VideoGame/BackToTheFutureTheGame'', the Creator/TelltaleGames PointAndClick game which takes place after ''Part III'' and acts as an unofficial fourth movie.
* ''ComicBook/BackToTheFuture'', the Creator/IDWPublishing comic that serves as an interquel for the series.
[[/index]]

!!Tropes? Where we're going, we don't ''need'' tropes!

[[foldercontrol]]

[[folder:Series-wide]]
* {{Adorkable}}: George [=McFly=]. Especially as a teenager, an ExtremeDoormat as an adult, walked over by everyone. A bit more of a smooth operator as an adult after Marty slightly alters the future, but as a senior in one possible timeline, prone to a [[CrackOhMyBack brittle back]].
* TheAllegedCar: The films don't hide the fact that despite the cool looks the Delorean DMC-12 was a troublesome car which broke frequently. It's particularly bad in the first movie, so maybe Doc worked some of the kinks out with the hover conversion?
* AlliterativeName: Marty [=McFly=]; Clara Clayton; Marty [=McFly=] Jr.; Marlene [=McFly=]; Maggie [=McFly=]; S. S. Strickland
* AllThereInTheManual: The FAQ included in the ''Back to Future III'' Blu-ray provides canonical answers to several questions viewers have come up with throughout the years (many of which can also be found on the [[Headscratchers/BackToTheFuture headscratchers page]] here), particularly those relating to various time travel paradoxes.
* AllThereInTheScript
** The names of the goons from Biff and Griff's gangs, as well as Lorraine's friends. The most easily recognizable is 3-D, wearing cardboard 3-D glasses in his youth, and aviators with red and blue lenses as a vice thug in the BadFuture.
** As well as other info of the characters' backgrounds. Including Doc's mother's side of the family growing up in Hill Valley.
* AlmostKiss: This happens three times in ''Part I'', between Marty and Jennifer (though they did share a brief kiss before she went home with her dad). Towards the end of ''Part III'', the two are finally able to kiss more definitively.
* AluminumChristmasTrees: The [=DeLorean=]. The [=DeLorean=] Motor Company went bankrupt in 1982, well before the film was made, and Robert Zemeckis had to argue with Universal to use the car since DMC wouldn't be able to give them any commercial endorsements. At the time the car was considered a failure; it's now entirely thanks to this series that anyone remembers it.
** The use of the word "Dude" as an insult in the 1885 segments. Back then it was pretty much equivalent to "City slicker" or "Dandy", and meant someone from an urban environment trying to play cowboy. (It is still used this way when referring to a "dude ranch".) Its use as a term of affection only goes back as far as TheSixties.
** An unintentional one occurs with the pronunciation of the word "gigawatt". The director's commentary notes that they were unaware that the word is pronounced with a hard "g" sound, hence the use of the pronunciation "jiggawatt" in the film. As it turns out, however, "jiggawatt" is the actual original pronunciation of the word and its use by the older and eccentric Doc Brown is rather believable.
* AppliedPhlebotinum: The flux capacitor makes time travel possible. Never mind figuring out how, it just ''does''. Lampshaded by Marty.
-->'''Marty:''' Flux capacitor... fluxing.
** In a piece of deleted dialogue, Doc goes in to slightly more detail about its function: "The flux capacitor stores energy and releases it, like a big lightning bolt."
* ArtisticLicensePhysics: They're time traveling. In a [=DeLorean=]. Physics in general takes a back seat to the plot, when it isn't given a total HandWave. (The hover-capable vehicles from 2015 in particular break the ''known'' laws of physics simply by working on antigravity.)
** ArtisticLicenseNuclearPhysics: not only an implausibly compact and overpowered fission reactor at the start, but the Mr. Fusion reactor from TheFuture is a mass-produced home appliance; not only that, but it clearly allows fusion of heavier elements (from household waste- not just stripped out hydrogen as the Doc adds a drinks can ''after'' emptying its contents) when, in RealLife, even stars are only capable of heavier than lead fusion in the moments before going supernova.
* BerserkButton
** "''Nobody''... calls me chicken." (With a variation in ''Part III'', where the equivalent word is "yellow") This particular berserk button appears to be subject to sequel retconning, as it is nowhere in evidence in ''Part I''. He did seem more willing to get into a fight than was sensible, but not directly from being called names.
*** Then again, nobody actually ''did'' call him a name in ''Part I''.
* BookEnds:
** The first time the [=DeLorean=] travels through time, it leaves its registration plate spinning on the spot behind it. After the [=DeLorean=] makes its final journey and gets destroyed by an oncoming train, the car's registration plate from 2015 is left doing the same thing.
** In the original film's climax, Marty returns to the shopping mall just moments before his past self warps to 1955. The only difference is he's returning to [[BrickJoke Lone Pine Mall, not Twin Pines Mall]].
** "The Power of Love" by Huey Lewis & The News is played in both the second scene of the first film, and the second-to-last scene in the final film.
** Marty's first and last lines in the trilogy are "Hey, Doc?", though in Part III, Marty adds "Where are you going now, [[TitleDrop back to the future]]?"
* BrickJoke:
** In 2015, we find that Marty's future life is not going too well, the result of his life going down the toilet after a car accident when he got challenged by Needles, who called him "chicken" to a street race, in which Marty collided with a Rolls Royce and broke his hand, and the driver of that car pressed charges. Marty gave up on his music career and has been resorting to rather desperate means to stay afloat, to such that he agrees to participate in an illegal business deal with Needles after Needles calls him "chicken", and gets a bunch of YOU'RE FIRED!!! faxes from Fujitsu as a consequence. Then the main plot kicks in, which sends Marty and Doc back to Alternate 1985, then to 1955, and then to 1885 for the remainder of Parts II and III. When Marty returns to the present and picks up Jennifer, they are driving in Marty's new 4x4 pickup past the entrance to Hilldale, the neighborhood where the future Marty will live, and our Marty recognizes the place. Just then, Needles and some of his pals pull up alongside Marty and the "chicken" thing comes up. Marty looks like he's going to give in and race Needles, Jennifer desperately telling him not to... but when the light turns green, Marty floors his vehicle in reverse while Needles speeds forward. As Needles barrels down the street, he and his pals narrowly swerve to avoid an oncoming Rolls Royce making a left turn off a side street, and Jennifer realizes it's the car Marty would have hit.
--->'''Jennifer:''' ''(as they both watch Needles race off)'' Did you do that on purpose?!
--->'''Marty:''' Yeah; [[CharacterDevelopment you think I was stupid enough to race that asshole?]]
** In ''Part I'' Doc holds his experiment at the '''Twin Pines''' Mall, casually mentioning it used to be farmland, and that the owner tried to breed pine trees. When Marty travels back in time, he ends up on Old Man Peabody's farm, also known as Twin Pines Ranch. When Peabody begins shooting at Marty with his shotgun, Marty is forced to flee towards the road. As he's driving, notice that there are twin baby pine trees next to the dirt path, fenced in to protect them. In fleeing, the car ends up smashing through and destroying one of the two trees. Over an hour later, we find ourselves back at the beginning, only this time we're at '''Lone Pine''' Mall, implying that Peabody did not try to replace the pine tree that was destroyed.
** The name of Clayton Ravine: Marty says that it's named after Clara Clayton, who fell to her death there -- at least, she did until the Doc rescued her. When Marty returns to the future, the ravine is now named Eastwood Ravine, presumably to honor Marty (going by the name of "Clint Eastwood") who had faced down the robber and murderer Buford Tannen before (as far as they knew) dying in the ravine.
* BulletProofVest: In all three movies; they seemed to like this trope. In real life, only Marty's improvised "stove-door vest" out of the ''Dollars'' trilogy in Part III would have worked; the high-velocity rounds from the Libyans' AKM would have torn through Doc's vest like it wasn't even there.
* BurningRubber: The [=DeLorean=] leaves twin trails of fire in the "old" time period after it jumps to the "new" time period. It does this even when it's flying.
* ButterflyOfDoom: Most of the first film, and much of the sequels. Namely, thanks to old Biff handing that almanac to his 1955 self, A-Biff was able to affect history enough that in 1985, Nixon was in his fifth term as President, and the Vietnam War was still ongoing.
* CallBack:
** Several set pieces (such as a Tannen and his gang chasing Marty in front of the ClockTower) are reused throughout the trilogy, to show that history repeats. {{Lampshaded}} by 2015 Biff: "There's something very familiar about all this."
** The fundraisers trying to save the clock tower did, indeed, manage to save it.
** Doc justifies sending Marty to 1885 in the middle of the desert by saying "You don't wanna crash into a tree that once existed in the past". In the first film, one of the first things Marty did after arriving in 1955 was (accidentally) run down one of Old Man Peabody's twin pines.
** When Doc Brown makes a model of Hill Valley in the first movie, he apologizes to Marty that "this is not to scale." Lampshaded in the third movie when Marty interrupts him and says, "Yeah, I know. It's not to scale."
*** Immediately following the scene where they plan up their escape on a scale model of Hill Valley, a girl is going to pay them a visit, upon which they need to hide the [=DeLorean=]. In the first movie, it's Marty's mother Lorraine asking him to go with her to the ''Enchantment under the Sea'' dance, while in the third movie, it's Clara Clayton asking Doc to go with her to the inauguration festival of Hill Valley's clock tower, with the pretext of asking him to fix her telescope.
** In all three films Marty wakes up in bed, believing his time-traveling escapades have been a nightmare. He is comforted by a character played by Lea Thompson (Marty's mother Lorraine in 1 & 2, his great, great grandmother Maggie in 3) by being told he's safe and sound in some place that jars him and reminds him it's not a nightmare after all.
** The Tannen family has every reason to hate manure.
** A blink-and-you'll-miss-it example occurs in the second film when Marty (indirectly) causes damage to Griff's car. Marty had previously done so to Biff's car in 1955, though in a different manner.
** In ''Part I'', Biff Tannen crashes the [=McFlys=]' car while drunk driving and forces George to pay for not only the damage to the car, but also the cleaning bill for his shirt ("I spilled beer all over it when that other car smashed into me"). In ''Part III'', Buford claims his horse threw a shoe while he was riding it and demands that Doc (who shoed the horse) should pay not only for the horse (which he shot in a rage), but for "the perfectly good bottle of fine Kentucky Red-eye" he was holding at the time.
** In the third film, before he gets out of bed at the [=McFly=] farm in 1885, Marty stops to make sure his pants are on, after Lorraine removed his pants in 1955.
** In the first film, Doc's attempt to demonstrate how Marty will get back to the future with a model of the city and a wind up car goes awry, and the car catches fire. In the third film, the model is still set up in Doc's lab, and Marty pulls the scorched car out of a wastebasket.
* CarFu: In ''Parts I'' and ''II'', Biff tries to run Marty down with his car. Both times he crashes into a truck carrying large amounts of manure.
* {{Catchphrase}}:
** Doc's "Great Scott!" and Marty's "This is heavy!" Inverted in ''Part III'', where they once exchange lines.
** In the second and third films, Marty also developed the Catch Phrase "Nobody calls me chicken!" (or "yellow" in the Western setting) in response to his personal Berserk Button.
** Also hilariously lampshaded in the first film: "Weight has nothing to do with this!", "There's that word again, 'heavy'. [...] Is there a problem with the Earth's gravitational pull?"
** In the second and third films, Biff and Buford have good reasons to say,"I hate manure." His gang also subverts this in the first movie when they collide with the manure truck with a cry of "SHIIIIIIIIIIIT!"
** Strickland seems to think that ''everyone'''s problem is that they're a slacker. Drive-by shooters peppering his home with bullets? Well, EAT LEAD, SLACKERS!
** Marty's variations on "What the hell is that?" followed by a punch.
** Various Tannens as well as Vice Principal Strickland tend to refer to Seamus, George, Marty, and Marty Jr. by their last names.
** "You're the doc, Doc."
* CelebrityEndorsement: Michael J. Fox, and Pepsi. (Which he has difficulty ordering.)
* ChangedMyJumper: Marty's clothes in both 1955 and 1885 cause people to remark about them.
* ChekhovsBoomerang: The hover board, particularly the fact that its owner lets Marty keep it. After it's initial scene, it doesn't appear until later on when Marty needs to use it to get to the almanac from Biff. In the third film, the viewer is reminded a few times before Marty goes to 1885 that he still has it, and ends up using it so that Doc can save Clara.
* ChekhovsGag: The jokes about Uncle Joey.
* ChekhovsGun:
** If you see a manure truck anytime during the trilogy, a Tannen is ''SURE'' to get covered deep in it before the movie's end.
** The hover-board: used in the second film multiple times (and in different eras), the device is used again (by Marty) to save Doc and Clara during the climactic train sequence in the third film.
** The giant speaker seen at the beginning of the first movie is months later used in the beginning of Episode 1 of Back To The Future: The Game by Marty to get Doc's notebook back from Biff.
** Marty's "auto accident": first referred to in ''Part II'' (during the 2015 segment), then narrowly averted during the finale of ''Part III''.
** In ''Part II'', Marty watches a scene from ''Film/AFistfulOfDollars'' during the 1985-A segment (at Biff's Casino). The scene is question is the part where Clint Eastwood uses steel plating under his poncho to protect himself during a gunfight. Marty then uses this trick (with a boiler plate) in ''Part III'' to survive his confrontation with Mad Dog Tannen.
* ChekhovsSkill:
** Marty holding onto cars while skateboarding (skitching) in ''Part I'', he uses the same trick (on a hover-board) in ''Part II'' to steal the Almanac from Biff, and to Travel along a train in ''Part III''.
** In ''Part II'' Marty demonstrates his skill with a gun-based arcade game. This becomes important in ''Part III'', giving him a sporting chance in an [[IKnowMortalKombat actual duel]]. [[spoiler: This is subverted when he removes his gun-belt and lets Buford shoot him in the boiler plate he wears under his poncho -- [[CurbstompBattle then beats the shit out of him]]. Also deconstructed by the reason he needs to pull this off- the gravestone photograph shows it would not be enough to save him from an experienced killer like Buford Tannen]].
* ClockTower: Which is used in the [[RaceAgainstTheClock clock tower finale]].
* CloseEnoughTimeline: There are not too many changes to 1985 when Marty returns there in ''Parts I'' and ''III''.
* ColourCodedForYourConvenience: The [=DeLorean=]'s LED displays are red for "Destination Time", green for "Present Time", and yellow for "Last Time Departed", in homage to ''[[Film/TheTimeMachine1960 The Time Machine]]''. In ''Part III'', Doc has made presto logs, color-coded green, yellow and red, in increasing order of the amount of heat each produced to make their train run faster, with a corresponding gauge showing when it would happen.
* ComesGreatResponsibility: Doc eventually comes to view the [=DeLorean=] as a menace. Considering it's a device that if misused has the potential to ''undo the universe'', he's not far off.
* CompressedVice:
** Marty's "chicken" problem, a key element of the sequels, is never even referred to in the first film. But to be fair, nobody calls him such a name in the first film either.
** Related is that in ''Part I'', Marty is concerned that nobody will like his audition tape. At the start of ''Part II'', Marty simply assumes he'll become a rich rock star. [[FridgeBrilliance Possibly due to being raised by more supportive parents in this timeline?]]
* ContrivedCoincidence: Doc Brown had the revelation for the flux capacitor on the exact same day Marty's parents met. Exactly one week later on November 12, there was the school dance where the two kissed for the first time, and lightning stuck the clock tower. It also happens that the day of the school dance was also the day Old Biff traveled back in time to change the past. This is virtually [[LampshadeHanging lampshaded]] in the second film.
-->'''Marty:''' That's right, Doc. November 12, 1955.\\
'''Doc:''' Unbelievable that old Biff could have chosen that particular date. It could mean that that point in time inherently contains some sort of cosmic significance. Almost as if it were the temporal junction point for the entire space-time continuum! On the other hand, [[LampshadeHanging it could just be an amazing coincidence]].
** A deleted scene from II shows future Terry - The mechanic who originally cleaned and fixed Biff's car in 1955 - complaining to future Biff about the money that Biff never paid him for cleaning it. Terry specifically mentioned the day that he returned the car to Biff - November 12th, 1955. Biff could have easily picked another day to come back to, but it's possible that future Biff chose that specific day because it was fresh in his mind, not to mention it was the day that George punched him out, which changed his life forever, and didn't anticipate that Marty would just directly ask alternate-timeline Biff what day it was.
* CoolCar:
** The [=DeLorean=]. Anyone who grew up in TheEighties and enjoyed the ''BTTF'' movies will invariably hold a sort of unrequited love for them, even though in their unmodified form they're underpowered and don't handle too well. (Arguably, that's part of the joke -- getting a real [=DeLorean=] up to 88 miles per hour is about as likely as getting it to travel through time.) In fact, the car is so iconic that these days it's practically impossible to look at a [=DeLorean=] without thinking of these movies.
** Other examples: Biff's '46 Ford Super [=DeLuxe=] convertible, Marty's tricked-out 1985 Toyota 4x4, and Doc Brown's 1948 Packard Victoria convertible (of course, to a car buff, almost ''every'' car you see in the 1950's segments would qualify).
* CoolOldGuy: Doc Brown, the only scientist to believe in quantum physics, and the only one to communicate with his past self.
* CoolShades:
** Doc's steel glasses at the end of ''Part I'', used in ''Part II'' when he flies the [=DeLorean=].
** Also, Marty used sunglasses as part of his "Inconspicuous" '50s clothes.
* CoveredInGunge: "Manure. I hate manure!"
* DavidVersusGoliath: George vs. Biff in the school parking lot. Or, alternatively, Marty vs. Biff and his assorted relatives
* DeadpanSnarker: Marty. Doc can be it as well, but not on Marty's levels.
** Linda, based on the few scenes we see her in, also appears to be this.
* DeliberateValuesDissonance:
** In the first film, "A colored mayor? That'll be the day..." after Marty recognizes the malt shop's janitor is the future mayor Goldie Wilson.
** In Part III:
*** "What's that writing? Nee-Kay? What is that? Some sorta injun talk or somethin'?"
*** "Tannen bragged that he killed 12 men, not counting Indians or Chinamen."
*** "Musta got that shirt off'n a dead Chinee."
* DinerBrawl:
** At least as far as ''Part I'' and ''II'' are concerned, every time a [=McFly=] (or two) goes to the local diner, a Tannen is sure to be there with his cronies to cause grief along for the victim.
** Part III also invokes the trope, though in a saloon instead of a diner, as evident when Buford walks into the bar and mistakes Marty for Seamus.
* DoubleVision: Used frequently and well.
* DramaticIrony: Due to the time-travel heavy plot, we get a lot of this.
* TheEighties
* EinsteinHair: Doc. And in a way, Einstein the dog...
* EveryoneWentToSchoolTogether: George, Lorraine and Biff. [[JustifiedTrope Justified]] by Hill Valley being a small enough town for this to be likely.
* EverytownAmerica: Hill Valley.
* EstablishingCharacterMusic: The first time we see Marty [=McFly=], he walks into Doc Brown's laboratory, plugs in his guitar, and begins shredding. This quickly establishes him as a laid back, average teenager.
* ExtyYearsFromNow: Thirty years in the past; thirty years in the future; then a hundred years in the past.
* FakeShemp: George [=McFly=] in the sequels. Any shot of him is either a lookalike (faraway, or upside-down) or stock footage from the first film.
* TheFifties
* FishOutOfTemporalWater:
** Marty, everywhen but 1985. In a way, he was also one of these in 1985-A!
** Inverted with Doc, he seemed to fit in better in 1885 and was a respected member of the community (as opposed to the crazed crackpot rep he had in 1985).
* FlashbackWithTheOtherDarrin:
** The ending scene of ''Part I'' is also the opening scene of ''Part II''. Since Elisabeth Shue had replaced Claudia Wells as Jennifer, the scene was refilmed for the sequel. The re-shot version is nearly identical, with the only difference being that Doc Brown's face is shown this time, he gives a significant ''look'' with his eyes, and [[HesitationEqualsDishonesty hesitates slightly]] before responding to Marty asking whether he and Jennifer end up as "assholes". You'll notice that [[TheyJustDidntCare they didn't even bother to match Shue's hairstyle with Wells']]. Sure, most people didn't notice at first because of the four-year lag in RealLife, caused by Robert Zemeckis being off shooting ''Film/WhoFramedRogerRabbit'', but if you watch the two films back to back it can be pretty jarring.
** Crispin Glover also didn't return, so in all refilmed 1955 scenes in Part II, George is always seen from behind (except one shot of recycled footage viewed through Marty's binoculars).
** The SpearCarrier couple ("Who is that guy?" "That's George [=McFly=]...") also get replaced in ''Part II'''s 1955 scenes, as do most of the other 1955 extras.
** Speaking of 1955 extras, the character Lester ("I think he took his wallet") was played by an unnamed extra in ''Part I'', who could be seen crouching over Biff. Obviously, as Lester became a marginally AscendedExtra thanks to Marty's interference in ''Part II'', he was Other Darrin'd for the sequel.
* FlyAtTheCameraEnding:
** The first ''Back to the Future'' ends with the [=DeLorean=] flying up in the air, turning around, then warping through time just as it hits the camera.
** The third movie [[CallBack ends the same way]], [[spoiler:except with the train in the place of the [=DeLorean=]]].
* {{Foreshadowing}}: And plenty of it.
* FutureLoser: Everyone at one point, notably Biff and Marty.
* GangOfBullies: Biff, his ancestors, and his successors lead a small group of thugs.
* {{GASP}}: Doc Brown. Doubles as an ActorAllusion for Creator/ChristopherLloyd who has done it in several other movies.
* GenerationXerox: Many examples.
* GoldfishPoopGang: Young Biff's greaser cohorts. They go by the names of "Match" (Billy Zane, playing a goon with an OralFixation), "3-D" (wearing 3-D movie glasses), and "Skinhead" (the one with a crew cut). The trio is still in Biff's employ in 1985-A, now working as corrupt security guards at Biff's Pleasure Palace; Match now sports a ten-gallon hat and bolo tie, Skinhead's gone grey, and 3-D has swapped out his eyewear for [[AndyKaufman Tony Clifton]] sunglasses.
* HairTodayGoneTomorrow: Subverted with Strickland in ''Part I'' as he is shown to be bald in 1985, and in the 1955 scenes, it's seen his receding hairline is on its last legs. Double subverted with the marshal in ''Part III'' as the marshal is an ancestor of Strickland's.
* HeroStoleMyBike: ...or hover-board. At least Marty gives it back afterwards.
-->"Keep it. I got a ''Pit Bull'' now!"
* HeterosexualLifePartners: Marty and Doc, "Partners in Time". And ''how''. In the first film, Doc [[HeroicSacrifice sacrifices himself]] to save Marty from the Libyans, and Marty returns the favor by ensuring that he gets the news of his impending death. Throughout the entire trilogy, they're by each others' sides, protecting each other and providing the fandom with many crowning moments of heartwarming.
** In the third film, despite explicit instructions in Doc's [[WriteBackToTheFuture letter]] ''not'' to go back for him in 1885, Marty decides to risk his life to go back anyway after stumbling upon Doc's tombstone that reveals he was killed by [[IdenticalGrandson Buford "Mad Dog" Tannen]] less than a week after sending the letter. And when Doc sees him, he only gives a quick "I specifically told you ''not'' to come back for me," before admitting he's very happy to see him.
* HiddenDepths: A recurring theme.
** ''Part I'' gives us George, who starts out as a nerdy loser. Marty is surprised to find that George was very creative as a teenager, and ''everyone'' is shocked that George has it in him to stand up to Biff.
** Played straight in ''Part III'', where we find that the eccentric Doc Brown is quite charming when around his love interest, and is a pretty good dancer to boot. {{Lampshaded}} by Marty:
-->'''Marty:''' The Doc can ''dance''??
** Marty himself throughout the trilogy. He may be BookDumb, but Mrs. [=McFly=]'s boy can handle the practical intelligence needed to outsmart opponents and operate time machines any day.
* HighConcept: One of the average film critic's examples -- normally on the level of "Young man goes back in time and {{Grandfather Paradox}}es himself, has to play cupid to his own parents."
* HighSchoolDance: The Enchantment Under The Sea Dance.
* HighSchoolRejects: Biff, in the "Lone Pine 1985/2015."
* HighSchoolSweethearts: Marty's parents and Marty himself with Jennifer -- though the first time we see either marriage, neither is especially happy. Both (implied for the latter) end up being HappilyMarried thanks to time travel and CharacterDevelopment.
* HilariousOuttakes: On the DVD release.
* HistoricalInJoke: Plenty of them. Parts ''I'' and ''III'' show the "real" origin of rock-and-roll music, skateboarding and Frisbee discs.
* HistoryRepeats
* HomemadeInventions: Doc has a passion for making these. The time machine being the prime example, more minor examples including a robotic dog-feeder, humongous amp, a mind-reading machine which doesn't work, and a steampunk ice-maker.
* HonorBeforeReason: Marty is guilty of this due to his BerserkButton of being called cowardly in any way. This has done ''nothing'' but gain him more trouble than necessary and making things more difficult than they were before.
** Future Marty ''knew'' that Needles' proposition was illegal and that he could get fired if he went through with it, but does so anyway when called a chicken. Of course, Future Marty is indeed found out, immediately, by his employer (who was monitoring the call!), whose response is to send out a bunch of faxes reading "YOU'RE FIRED!!!"
** This almost gets Marty killed in ''Part III'' until Seamus and even Dr. Brown called him out on his stubbornness to not accept being called cowardly.
* HoverBoard: Picked up in 2015, used in both 1955 and 1885.
* HubcapHovercraft: The [=DeLorean=] receives this upgrade at the end of the first movie.
* IdenticalGrandson: Michael J. Fox, Lea Thompson, Thomas J. Wilson, and some of the minor characters all wind up portraying their own ancestors/descendants. [[UpToEleven Including Michael J. Fox in drag playing an Identical Daughter]]. Lampshaded in Part III, after Buford mistakes Marty for Seamus [=McFly=], says "You ain't Seamus [=McFly=]... you look like him, though."
* IfMyCalculationsAreCorrect:
** "...when this baby hits 88 miles per hour... you're gonna see some serious shit."
** "...you will receive this letter immediately after you saw the [=DeLorean=] struck by lightning"
* IKnowMortalKombat: Marty is a crack shot, thanks to whiling away his youth playing ''Wild Gunman''. Established and mocked in the second, used straight in the third.
** Though "used straight" applies only to the fairground shooting gallery- [[spoiler: as the changing gravestone picture shows, it would ''not'' have been enough to save Marty in a straight-up duel with Buford "Mad Dog" Tannen, a hardened killer]].
* ImmediateSequel: ''Part II'' and ''III'' literally begin seconds after the previous ones, ''II'' after ''I'', and ''III'' after ''II''.
* ImMrFuturePopCultureReference:
** "Calvin Klein" is actually a subversion, as Lorraine [[LineOfSightName sees it written on Marty's underwear]] and believes it's his name. Marty does correct her but she still calls him Calvin. Marty bemusedly goes with it to avoid arousing further suspicion.
** Marty intimidates George into asking Lorraine out by posing as "[[Franchise/StarWars Darth Vader]]", [[Film/ETTheExtraTerrestrial an extra-terrestrial]] from [[Franchise/StarTrek Planet Vulcan]].
** "Clint Eastwood", on the other hand, is played completely straight. Marty can't even back out of a duel because not only would it tap his personal BerserkButton, but it would also preemptively ruin [[Creator/ClintEastwood the actor]]'s career in Westerns by associating his name with cowardice, and keep the ''Dollars'' trilogy or ''Franchise/DirtyHarry'' from featuring him.
* IncorruptiblePurePureness: George [=McFly=]. As nerdy as he is, he is very nice and won't fight the bullies because he feels it is wrong. Also, Jennifer Parker. She is the sweet, supportive, quiet girlfriend and later, wife of Marty [=McFly=].
* IntergenerationalFriendship: Marty and Doc. {{Word of God}} explains that the friendship started when Marty was around 13-14 years old. After being told for years that Doc Brown was a dangerous, crackpot, lunatic, he snuck into Doc's lab to see for himself and instead was fascinated by what he saw in there and thought Doc's inventions were cool. Doc found him and was happy Marty thought he was "cool and accepted him for what he was". Doc then gave Marty a part-time job helping out with experiments, helping in the lab, and feeding Einstein. [[http://www.mentalfloss.com/blogs/archives/97285 Read for yourself]].
** In Part III Marty befriends his Great-Great Grandfather Seamus. Seamus isn't much older than Marty during the time period though.
* InTheBlood: The Tannens.
* ItRunsOnNonsensoleum: It's never really explained how the Mr. Fusion device Doc adds to the [=DeLorean=] from 2015 is able to generate the requisite 1.21 gigawatts of energy -- not to mention undergo nuclear fusion -- using an aluminum can and some other bits of garbage, though it's possibly supposed to be a comic-book style of fusion that turns matter directly into energy.
** ahem, the calculations have been run. Seeing as 1 GRAM of Hydrogen can produce 1 gigawatt, nearly enough to fuel the Delorean, a banana peel should be more than enough.
** It's also never explained why, in a future where such a compact and effective power source exists, 2015 technology couldn't simply modify the [=DeLorean=] to operate entirely on Mr. Fusion's energy along with the hover conversion and eliminate the need for gasoline (not to mention other cars--why were there even gas stations in 2015 when Mr. Fusion devices were readily available?).
* ItsTheJourneyThatCounts: The final [[AnAesop Aesop]] of the series, and the reason why the RetroactivePreparation trope is never invoked. Marty learns about his family and himself over the course of three films, things that he would have never discovered had he not been stranded twice.
* JerkJock: Biff Tannen primarily, but [[InTheBlood also Buford and Griff]].
* JustEatGilligan: A lot of complex plots and quick thinking [[JustifiedTrope have to be used]]; the simple solution cannot because it might cause a TemporalParadox, although eventually both Marty and Doc choose ScrewTheRulesImDoingWhatsRight instead. Part of the adventure is the lengths the characters have to go to in order to preserve the timeline(s).
* LadyDrunk: Lorraine, at the start of the first film and during the 1985-A scenes of the second film.
* LargeHam:
** Christopher Lloyd in spades.
** Most versions of Biff to a certain degree, but none more-so than his future offspring Griff.
* LaserGuidedKarma: For all the crap Biff and his family line tries to pull to Doc and Marty throughout the course of the trilogy, there is always a cart of manure placed just at the right moment to deliver Tannen some sweet, stinky justice.
* TheLawOfConservationOfDetail: The first twenty minutes or so of ''Part I'', as well as 2015 [=McFly=] house portion of ''Part II''.
* LightningCanDoAnything
* LikeFatherUnlikeSon:
** George [=McFly=] in the original timeline was a spineless geek who let Biff Tannen continue to bully him even after they graduated high school. George's son Marty is a cool but hot headed kid who stands up to bullies especially if [[BerserkButton they call him chicken]].
** Marty's own future son is also a contrast to himself. Whereas Marty stands up for himself and has some smarts in him, his future son is a pushover and appears to be a bit of a dumbass.
* ALittleSomethingWeCallRockAndRoll: The Johnny B. Goode scene in ''Parts I'' and ''II''.
* TheLoad: Jennifer Parker. Bob Zemeckis and Bob Gale never had a character development in mind for her, stating that had they planned to make a sequel to the original film, they would not have put "the girl" in the car at the end. Sure enough, less than five minutes into ''Part II'', she's sedated and pretty much spends the rest of the series that way, while Doc outright admits she's no use to them, he just had Marty bring her along because she'd already seen the time machine. Neither Claudia Wells in the first movie nor Elizabeth Shue in the others are even given top billing in the film credits, even though those who play even smaller roles are.
-->'''Marty''': What did you bring her for?!
-->'''Doc''': I had to do something, she saw the time machine, I couldn't leave her with that information! Don't worry, she's not essential to my plan.
* LookBehindYou: Works on most Tannens, although Griff's gang in part 2 has some really neat cybernetic implants. He almost seems a bit surprised when he looks back and finds that his hand has caught Marty's fist. Also doubles as SchmuckBait.
* LostInTranslation: Most of the humor relating the fact the time machine is a [[TheAllegedCar crappy car for Americans]] is lost for foreign ones as that brand [[NoExportForYou was never exported outside the U.S. since the company went bankrupt in 1982]] so many foreign audiences got puzzled when Doc Brown explained about why a [=DeLorean=], a modern car, could lose a duel against a very old car.
** In the Italian version, for some reason unknown to mankind the Flux Capacitor got mistranslated as "flusso canalizzatore", which roughly means "channeling flux" and has almost nothing to do with the original name; however, in the third movie, Doc's letter talks about the broken "condensatore di flusso", which is an exact translation of "flux capacitor"; the Italian audience was never able to understand what this "condensatore di flusso" was and why would it be of any importance.
* MadScientist: Emmett Brown is the poster child for this trope, but only when he's inventing or planning; because of great writing it's just one facet of his character. He can also be quite lucid and/or calm.
* {{Malaproper}}:
** Biff Tannen: "Make like a tree and get out of here!" {{Lampshade|Hanging}}d by none other than the Biff Tannen from 2015: "You sound like a damn fool when you say it wrong!"
** In the now-closed theme park ride, 1955 Biff uses marbles to trip up the security staff coming after him and gleefully quips "Have a nice trip, see you next winter!" As he runs off, one of the fallen men says "It's 'see you next '''fall''''!"
** Biff thinks pointing out his malapropisms is about as funny as a screen door on a battleship!
** Buford Tannen in ''Part III'' is also prone to this:
-->'''Buford:''' (''to Marty'') Eight o'clock Monday, runt! If you ain't here, I'll hunt you and shoot you down like a duck!\\
'''Gang Member:''' It's dog, Buford. Shoot him down like a ''dog''.
* MeanCharacterNiceActor: Thomas F. Wilson. HUGE example. He is a very nice guy in real life (don't ask him to call someone a butthead). He actually drew on his real life experience from BEING bullied to play Biff.
* MeaningfulName: The '''strict''' ''Strick''land family line (and how!).
* MenActWomenAre: With the exception of 1955 Lorraine in Part I, female characters are only there to serve as {{Satellite Love Interest}}s and victims to male characters. In fact, they had to basically write around Jennifer Parker because she was brought to the future in the end of the first film, but when they actually started making the second film they realized they did not know what to do with her. Rather then {{Retcon}} her away, they solved this problem by making her stay sedated for much of the 2015 scenes. See the entry under TheLoad.
* MisterSandmanSequence: The TropeNamer, at least once in each movie, after Marty arrives in a new time period. It is to show what Hill Valley looks like in 1885, 1955, or 2015.
* ModelPlanning: A RunningGag. Doc Brown builds elaborate models of city blocks or canyons to demonstrate his plans to Marty, then apologizes for "the crudity of the model". It also catches on fire, repeatedly.
-->'''Marty:''' You're really [[ThisIsGonnaSuck instilling me with a lot of confidence]], Doc.
* MyCarHatesMe: The [=DeLorean=] has a tendency to fall into disrepair at the exact moment Marty lands in another time period. Sometimes, however, [[JustifiedTrope justified]]: in the first movie, the plutonium needed to power the flux capacitor isn't available, and in the third movie, the fuel line is damaged during an Indian pursuit and the gasoline leaks out, which the car needs to accelerate. The [=DeLorean=]'s habit of stalling in the middle of a road has prevented possible time paradoxes: In the original movie, Marty is forced to disguise the car behind a billboard, being unable to drive it openly through 1955 Hill Valley. By stalling right before the final run towards the clock tower it delayed Marty about 30 seconds; if he had started driving when the alarm went off he would have beat the lightning bolt and been stuck in the past for the rest of his life. At the end of the film, the [=DeLorean=] stalls ''again'', preventing Marty from interrupting the shootout at Lone Pine Mall (thus avoiding direct contact with his past self).
* NewspaperDating: Marty in 1955 and 1985-A, Doc in 2015.
* NiceJobBreakingItHero: Oh so very much. It seems like poor Marty can't go long without accidentally making the timeline worse thus requiring the need to undo the damage. "Saving" George from being hit by the car in ''Part I'' and buying the Sports Almanac in ''Part II'' were probably the worst cases. Not to mention any time Marty loses it whenever he gets called "chicken", which ends up making most situations twenty times worse.
* NobodyCallsMeChicken: Marty's besetting flaw is that he'll do anything rather than be called chicken.
* NoodleIncident: Uhm, Uncle Joey. It's never revealed on-film just why he's in prison, although a commemorative cover of ''USA Today'' [[http://www.polygon.com/2015/10/21/9578593/back-to-the-future-usa-today-front-page released in 2015]] (as in the actual date) suggested it was racketeering. (Not likely something that would cause a parole board to reject ''twelve'' attempts at parole.)
* NoCommunitiesWereHarmed: Outside of the iconic Universal Studios clocktower square set, "Hill Valley" is a mix of various [[SoCalization SoCal]] communities. The zip code on Marty's fax is the same as Caspar, California.
* NoManShouldHaveThisPower: Doc Brown repeatedly promises to himself to destroy his own time-traveling technology, which finally happens at the end of ''Part III''. [[spoiler:(And then it almost immediately turns out that he had built a new one.)]]
* NoPronunciationGuide: For "gigawatts". Not so noticeable to the general public at the time, but over 20 years on, the prefix "giga-" (beginning with a hard "g") [[TechMarchesOn has become commonplace]] for computer-related terms[[note]](Gigabyte and gigahertz likely being the most commonly known among the average computer user)[[/note]], so nowadays it's bound to give even non-engineers pause. (Or, make people think you're referencing ''Back to the Future''...)
* OddFriendship: Marty and Doc.
* OmnidisciplinaryScientist: Doc Brown. He even identifies himself a "student of all sciences" in the third movie.
* OncePerEpisode: All films have Marty being chased by a Tannen, a Tannen covered in manure, Marty thinking it was AllJustADream, a establishing shot of Hill Valley...
** The clock tower scene.
** Doc has the closing line for each film. In Part I, he tells Marty [[QuipToBlack "Roads? Where we're going, we don't need roads."]], in Part II, the 1955 Doc says "Great Scott!" when he encounters Marty ''just'' after sending the Marty from the first film back to 1985, and in Part III, he says "Nope, already been there." when Marty asks whether he's going [[TitleDrop back to the future]].
* OohMeAccentsSlipping: Creator/MichaelJFox's [[CanadaEh Canadian accent]] sometimes slips in as Marty.
** In Part I, when Doc asks Marty [[WhatDoesSheSeeInHim how Lorraine and George ever got together]], Marty says "I guess she felt sorry for him...", pronouncing "sorry" as "soory".
** In Part II, when he says [[HeroStoleMyBike "I need to borrow your... Hover-board?"]], he pronounces "borrow" as "boorow".
** Also in Part II, Marty notes that "This is to''moor''ow's newspaper."
* OurTimeMachineIsDifferent: Because it is a car, and a cool one at that.
** The time-traveling steam locomotive at the end of Part III, ''which also flies''!
* PercussiveMaintenance: Marty bashes his head against the [=DeLorean=]'s steering wheel when it refuses to start. At this, the ignition miraculously turns on. Doc is also seen giving his timer readout a whack in ''Part II'' when it flickers "1885"; he becomes stranded in that time period when lightning strikes the car.
* PickOnSomeoneYourOwnSize: Tom Wilson jokingly described the Tannen clan as evil incarnate, though that's not far off. Biff has tried to kill Marty twice, once in the past and again in an alternate reality. Buford spent an entire movie hunting him for no particular reason, really.
* PimpedOutCar: Doc made a time machine out of a car, and later a train, not to mention the flying abilities.
* PlayingGertrude: Lea Thompson is just nine ''days'' older than her onscreen son Michael J. Fox. Crispin Glover is actually three years ''younger'' than Fox, and Thomas F. Wilson is just two years older than Fox. This trope is played straight when it comes to scenes in 1985. But it becomes averted once we go back in time to 1955, where Thompson, Glover, and Wilson are playing their characters at or around Marty's age.
* ThePowerOfLove: Powerful enough to defeat {{Temporal Paradox}}es, apparently.
* PrettyInMink: In the first two films, there is a girl wearing a white rabbit fur shoulder wrap among the crowd gathering around a knocked-out Biff. This is notable for a couple reasons. One is that the actress is different in the two films, first a brunette and then a blonde. The second is in the first film she is amazed George finally stood up for himself, while in the second she's just in the background due to the point of view shift.
* PrinceCharmingWannabe: Biff with Lorraine in ''Part I'' and ''Part II''.
* ProductPlacement: Abound in the series. Often well-integrated into FishOutOfTemporalWater situations.
** Plenty from Pepsi, to the point it's amazing they didn't try to work it into Part 3. For a really good example, watch the scene between Marty and George just after the "Darth Vader" scene... notice that Michael J. Fox ''never'' completely covers the logo of his Pepsi bottle. Also, the writers had to fight to keep the "give me a Tab" gag in the first movie, because Pepsi didn't want Marty mentioning another company's soda. The futuristic Pepsi glass in ''Part II'' makes it look awfully good, though
** Ditto from JC Penney, which gets shown at least three times of the trilogy.
** Creator/{{Mattel}} and Nike get mentions in ''Part II''.
*** Mattel hasn't gotten around to making hover-boards...[[http://gizmodo.com/5965031/you-can-pre+order-the-back-to-the-future-hoverboard-right-now until they did]], '''[[{{Defictionalization}} just to mess with us]]'''.
*** Not to be outdone, [[http://www.pcmag.com/article2/0,2817,2392678,00.asp Nike introduced the same shoes]] that were worn or...uh, ''will'' be worn by Marty [[AustinPowers OH NO I'VE GONE CROSSEYED]]
** Doc Brown's JVC camcorder. Also, if you look closely, Marty Jr. and Marlene's phone visors have a JVC logo on the arms.
** An interesting case for Frisbee in ''Part III''; modern audiences will notice the ShoutOut to modern Frisbees with the pie tin, but [[http://en.wikipedia.org/wiki/Frisbie_Pie_Company Frisbie brand pies]] are still around as well.
** "Boy oh boy, Mom, you sure can hydrate a pizza." Yes, Lorraine, hydrate that Pizza Hut pizza in the Black & Decker hydrator. On a side note, Pizza Hut (at the time of production) was owned by Pepsi.
** Mr. Fusion is a riff on Mr. Coffee, one of those ubiquitous Eighties/Nineties appliances that nobody owns anymore. Alternatively, it could reference Mr. Transmission, an auto repair chain primarily in the South, but with franchises in California.
*** BlandNameProduct: In early concept art, Mr. Fusion was a [[http://logok.org/wp-content/uploads/2014/12/Westinghouse-Electric-logo.png Westinghouse]] product. When Westinghouse declined, the logo was [[http://backtothefuture.wikia.com/wiki/File:Mrfusion.jpg modified]], and the company became "Fusion Industries."
** A copy of ''USA Today'' is featured prominently as a RippleEffectIndicator in ''Part II''.
** "[[foldercontrol]]

[[folder: [[Computer Voice Thank you for using AT&T ]]
]]."
** The local Texaco station catches Marty's attention in 1955 when an army of servicemen come out to take care of one car. In 2015, Marty gawks at a giant robot operating the station.
** Forget West Point. To master firearms, visit your local 7-Eleven. Foreign dubs reference [[Ride/DisneyThemeParks Disneyland]] instead.
** The producers also put a Zale's Jewelry ad onto a Courthouse Square bench in ''Part I'', and Zale's neon signs in the 50s scenes of both ''Part I'' and ''Part II''. This was done mostly as a play on the names Zemeckis and Gale.
** The first piece of audio heard in the first movie is an ad for a Toyota dealer, which plays on Doc's radio. In 1955, this dealer instead sold Studebakers.
** During the pre-production of the first movie, someone negotiated an endorsement deal with the state of California's Raisin board that ''Back to the Future'' could do for raisins what ET had done for Reese's Pieces. He came back and told the writing staff that they needed Marty to habitually eat raisins throughout the film. The execution kept getting scaled back until the final inclusion of raisins was a single poster on the park bench the drunk is sleeping on when Marty returns to 1985. The California Raisin board was not happy and demanded their money back.
** A number of these instances were invoked, specifically the producers choosing brands whose 1955 logos were very different from their 1985 counterparts.
** Western Union will deliver a packet ''precisely'' when and where you ask. Even if it takes 70 years!
** An aversion whereas Mustang tried to get in on it only for the producers to fight for keeping the [=DeLorean=].
* TheProfessor: Doc Brown
* RaceAgainstTheClock: The clock tower finale for ''Part I'' reappears in ''both'' sequels, and ''Part III'' tries to outdo it with its own take.
* RealityEnsues:
-->'''Marty [=McFly=]:''' "There he is, Doc! Let's land on him, we'll cripple his car."
-->'''Doc:''' "Marty, he's in a '46 Ford, we're in a [=DeLorean=]. He'd rip through us like we were tin foil."
* RecurringLocation: Courthouse Square
* RecurringRiff: Each moment that something happens that changes time for the better (for example, when George defeats Biff and Lorraine falls in love with him, or when Marty retrieves the Sports Almanac with his hover-board) the series {{Leitmotif}} music signals the event.
* ReformedBully: Biff is a subverted example in the best timeline. He never becomes a great guy, but years of being under George's thumb have made him give up his meanest habits. However, him calling Marty "butthead" before he recognized him in the third film, and the behavior of his older self in the second might cast doubt on whether he's reformed or just scared of George.
* RescueRomance: George and Lorraine in ''Part I'' and ''Part II''; Doc and Clara in ''Part III''.
* RippleEffectIndicator: Varies by movie. Marty himself in ''Part I'', newspapers in ''Part II'', the tombstone in ''Part III''.
* RippleEffectProofMemory: Traveling through time in the DeLorean seems to shield Doc and Marty from changes in the timeline (even when not currently in the thing when an alteration occurs) for the most part, but not quite enough against things that would cause them to cease to exist entirely.
* RubeGoldbergDevice: Used by Doc in both ''Part I'' and ''Part III''.
* RuleOfCool: Doc made his time machine out of a [=DeLorean=] out of style. He does begin to mention that there was a reason based of the car's stainless steel construction, but is cut off before he can fully explain it.
* RunningGag:
** It doesn't matter what Marty and Doc do to the timeline for good or ill, Lorraine's brother Joey ''will'' end up a jailbird.
** Marty gets rendered unconscious, then wakes up to someone who isn't the mother he knows.
** Marty seems to wake up assuming he's at home with his mother. And of course always thinks it was AllJustADream. Then comes a WhamLine and he snaps awake, parroting the words that registered as jarring.
** And he sleeps in [[http://img2.wikia.nocookie.net/__cb20101206000617/bttf/images/4/41/Asleep.jpg a ridiculous position]].
** The Tannen name will be forever associated with open-top cars rear-ending manure trucks or simply taking a stumble into a manure pile, and yelling "[[VisualPun SHIIIIIIIIIIIT!]]" when the brown disaster is imminent.
** Doc Brown repeatedly [[TheKlutz falling over at the most bizarre times]].
** Marty's inability to get the fashions of the period right. Taken to the extreme with the cowboy outfit in ''Part III''. To be fair, in ''Part III'' the clothes are picked by 1955 Doc, and even Marty questions their authenticity.
** Whenever Marty finds himself in a new era or timeline, he can't resist walking aimlessly through the town square gawking, usually wandering right in front of an oncoming car (or carriage).
** Marty screaming helplessly as he enters into the a new time period because the [=DeLorean=] is often almost always about to crash into something upon arrival.
** Recurring family businesses, like the Jones manure truck.
** The Hill Valley clock tower is featured in each movie, sometimes pivotal to the story. In chronological order:
*** Part III shows its construction in progress in 1885, where Marty and Doc Brown appear in an antique photo by the clock face before it gets mounted. Said clock also designates 8:00 A.M. at the climax of the movie.
*** In Part I, during 1955, a fateful lightning bolt struck it and rendered it inoperable. This bolt was used to return Marty to the future.
*** Finally, in Part II, the tower has been renovated and restored to functionality as a respected landmark following the success of the petition, with a beautiful glass exterior. Until moronic Griff Tannen smashes through it on his hover-board like a bull in a china shop and receives the "I was framed!" headline in USA Today paper.
** The [=DeLorean=] continually breaks down and requires something to get it back to 1985.
** Freak lightning strikes causing things to stop working.
** The repeated appearances of the prematurely balding and irate Principal Gerald Strickland acting as the rigid authority figure, calling people, "Slackers!" In the third movie, his ancestor takes his place, minus the catchphrase.
** Marty sneaking around and then getting hurt in a way that would cause him to audibly scream, and he has to hold his tongue.
** Clint Eastwood movies and the usage of a bulletproof vest.
** Marty going by a ridiculous alias in each past time period, always someone far too notable in the present to be a watertight alias.
** Marty's egotistic nature getting the better of him at the slightest hint of being called cowardly, always luring him into making a huge mistake. Thankfully, [[CharacterDevelopment he gets over it]]. Ironically, his father starts off as timid until learning to be assertive, which later saves the [=McFly=] family from taking a lot of crap and going down the tubes. On the opposite end of things, Marty's future son is even more irrational and plucky, so the hot-blooded streak grows with each generation.
** A member of the Tannen family walking into the saloon/cafe, calling out at [=McFly=], and saying "I thought I told you never to come in here." Inverted with Grif in Part II, where Grif tells him to stay in the cafe instead.
* SayMyName: Doc and Marty do tons of this throughout the movies. And regardless of the decade, or even the century, Marty will be addressed by a Tannen with "'''''[[HeyYou Hey, McFly!!]]'''''"
** Even middle-aged Marty isn't free of this. He attempts to run a scam on his own company, only to find his irate boss lying in wait. "'''''[[JapaneseRanguage MACH FRY!!!]]'''''"
* SciFiWritersHaveNoSenseOfScale: Time travel needs 1.21 gigawatts -- the only source of which is supposedly [[DeusExNukina plutonium]] or a [[LightningCanDoAnything lightning bolt]]. A lightning bolt actually generates three whole orders of magnitude more power, peaking at just over one ''terawatt'', and plutonium fission is a possible, but extremely roundabout and expensive way of getting energy (you'd be much better of running a reactor that can get that kind of power from plutonium on uranium).
* ScrewDestiny: Prevalent throughout the series as Marty and Doc change reality by time-traveling, but comes to a head two times. [[spoiler: First, Doc, despite his misgivings, has his life saved - ''twice'' - by knowing how and when he is going to die, and Marty narrowly avoids a crippling accident that would change his life forever, thus changing the future they had just worked to save to the one we have now. At the very end of the trilogy, Doc says that it proves that there's no such thing as fate]]. Although the point about [[spoiler:Marty avoiding his accident]] is less Screw Destiny and more learning a lesson while in the past/future and avoiding the situation on his own.
* SecondEpisodeMorning: Numerous examples, including the "Mom, is that you?" scenes.
* SetRightWhatOnceWentWrong: A major theme in the trilogy.
* ShoutOut: Tons throughout the series.
** Two to ''Film/ChittyChittyBangBang'': Doc owns dogs named after famous scientists (Copernicus in 1955, Einstein in 1985), just like how Caractacus Potts owns a dog named after a famous inventor (Edison). And they both make flying vehicles. The time machine train in ''Part III'' even sprouts wings like Chitty.
** Another ''Chitty'' shout-out is how they both have breakfast-making machines in ''Part I'' and ''Part III''.
** The Y-shaped flux capacitor was designed to resemble an upside-down [[Film/TheAdventuresOfBuckarooBanzaiAcrossThe8thDimension Oscillation Overthruster]].
** Similarly, the [=DeLorean's=] requirement for 88 MPH was meant to resemble the [[Film/TheAdventuresOfBuckarooBanzaiAcrossThe8thDimension Banzai Institute logo]].
* SignatureTeamTransport: Doc Brown's [=DeLorean=] for him and Marty, of course. [[spoiler:And later, his time-traveling ''train'' for his whole family]].
* TheSlowPath: The [=DeLorean=] between ''Part II'' and ''Part III''. Also the [[WriteBackToTheFuture letter Doc wrote to Marty explaining the situation]].
* SnowballLie: Doc and Marty are the undisputed masters of using this technique to preserve their cover.
* TheSociopath: Biff is likely this.
* SophisticatedAsHell: Doc is comfortable with technobabble but also fluidly adopts Marty's vernacular whenever appropriate.
* SpearCarrier: Red the Bum, who calls Marty a "crazy drunk driver" towards the end of ''Part I'', and a "crazy drunk pedestrian" in the alternate 1985 in ''Part II''.
* StableTimeLoop: Interestingly, according to {{Word of God}}, as a general rule of thumb, the past is never "already altered" (hence the inclusion of YouAlreadyChangedThePast below). So officially, [[http://www.cracked.com/video_18203_why-back-to-future-secretly-horrifying.html if it seems like a time traveler has become the cause of something that already existed, he has merely replaced that cause]], [[RippleEffectProofMemory possibly using information gained from the result of a cause that now never happened]]. So originally, Clint Eastwood and Chuck Berry were truly original, Goldie Wilson came up with the idea to run for mayor himself, there wasn't a strange sequence of events at the 1955 school dance (let alone two), and Doc Brown was killed by Libyans. Then Marty happened.\\\
It's best explained, as the filmmakers do, by paying careful attention to the Clocktower. In the original timeline the stone ledge under the clock is perfectly intact only for it to be broken when Doc climbs up there during the climax. The ledge is broken in all subsequent appearances. So yes, there ''was'' an original timeline that Marty erased through his actions in the past.
* StockSoundEffects: BTTF ''loves'' Castle Thunder, especially in the first two installments. It appears literally dozens of times, mixed in different ways, during the big [[RaceAgainstTheClock Clock Tower Finale]].
* TakeThat: Biff Tannen and the Tannen family are named after then-Universal Studios executive Ned Tanen, who gave the Bobs a hard time during the making of their previous movie ''I Wanna Hold Your Hand''.
* TapOnTheHead: Marty is knocked out by a physical blow in all three movies, and wakes up fine each time.
* TechnicolorScience: The lightning bolt.
* TechnoBabble: Lampshaded. "English, Doc!"
* ThatWasNotADream: [[OncePerEpisode Once in all three films]]. In each one Marty gets knocked out and comes to in a dark room being nursed to health by a woman he thinks is the mother he knows, believing his recent hardships were a nightmare. The woman inevitably reassures him in a way that tells Marty (and the audience) that it actually wasn't a dream.
* ThemeNaming: Doc's dogs are named after famous scientists.
* ThemeTuneCameo: "The Power of Love" in all three movies.
* ThermalDissonance: The outer surface of the [=DeLorean=] comes out of a time jump extremely cold. If the air is humid, it promptly gets covered in ice.
* TimeIsDangerous: The [=DeLorean=] has to be traveling at 88 miles per hour. Which means that unless you know what's going to be in front of you when you arrive in the new timeline, you're going to crash. By the third movie, Doc seems to be acknowledging this. Marty's a little less sure, but both times Doc assures him that the obstacle he's seeing in the present won't be there in the destination time.
* TimeTravel: Of course.
* TimeTravelForFunAndProfit: Doc is the former, Marty and Biff seem to be the latter. Though Marty quickly gives up on the latter after Doc catches him red-handed and sermonizes him.
* TitleDrop: It's done several times throughout the course of the trilogy. In fact, it's become so common for Doc and/or Marty to drop the title that it's practically become a {{Catchphrase}} / BorrowedCatchphrase.
* ToiletHumour: All members of the Tanen family have a custom of crashing with manure trucks.
* ToxicFriendInfluence: Marty's "friend" Needles. Pretty much everything bad that happened to Marty in the original future was because of him. Although it's never stated that they're friends.
* TwoPartTrilogy: Although the first movie ends on a definite SequelHook, it can be clearly be enjoyed by itself. The second, however, ends on a clear CliffHanger that obviously requires a third movie in order to be resolved. Marty's "chicken" problem was also added for the sequels, as well as nemesis Douglas "[[Music/RedHotChiliPeppers Flea]]" Needles. Justified in that the second and third part were originally intended to be a single movie. And even after the split, they were still filmed back-to-back.
** Story-wise, however, it is somewhat of an inversion, as Part II & III are both quite distinct from each other. Part II (especially during the second half) ties in strongly with the first film, while Part III is more or less a separate story that just uses the events of the previous films to get things going.
* UncannyFamilyResemblance: Both the McFlys and Tannens have this across the board. The Stricklands do too.
* UnfamiliarCeiling: In every film, Marty wakes up with his mother (or great grandmother) ministering to him.
* VagueAge: Doc's age in 1955 and 1985 is never mentioned in the films. The fact that Christopher Lloyd looks exactly the same in both time frames doesn't help. He must be in his 80s in 1985.
** Fairly hilarious in that his age is referenced in Part II (with his "old" mask removal and his comments about having work done), so he didn't have to wear makeup. Yes, he really was given an age-up for the original 1985. Lloyd just has that old puppy dog face no matter what his age, apparently.
** In [[VideoGame/BackToTheFuture Back to the Future: The Game]], they go to the year 1931, and Marty meets a very young Emmett Brown (not even Doc Brown yet, as he hasn't got any kind of degree). Emmett confirms to Marty that he is, in fact, 17 years old. Do the math, and you see he was born in 1914. This makes him 41 in 1955 and 71 in 1985. There. You can stop losing sleep at night over this now.
* VillainDecay: Actually invoked with Biff. In the first film, he goes from being George [=McFly=]'s bullying co-worker to the family's submissive mechanic, all because of George's punch in the 1950s. He got worse in the sequel but went back to being subservient by the end of the third movie.
* WritersCannotDoMath: A stock [=DeLorean=] DMC-12 only got about 130 horsepower. It would go 0-60 in about a day and a half. That, of course, is before you dump a fusion reactor in the back seat, with the requisite lead shielding to keep everyone inside from dying of a radiation overdose, easily doubling the weight of the car. So the notion that the car ''ever'' got up to 88 is hilarious.
* {{Zeerust}}: Awesomely happens both in- and out-of-universe:
** In-universe, 1950s-Doc makes a series of hilariously bad predictions about the future
--> '''Doc''': "What on Earth is that thing I'm wearing?" (referring to the radiation suit he was wearing in the 1980s film to protect him from the Flux Capacitor)
--> '''Marty''': "A radiation suit"
--> '''Doc''': "Of course! Because of all the fallout from the atomic wars!"
-->'''Doc''': "I'm sure that in 1985, plutonium is available in every corner drugstore, but in 1955, it's a little hard to come by."
** Out-of-universe, we get to see what the film's creators envisioned for 2015. It, um... looks a little bit different than how things actually turned out ([[IWantMyJetpack seriously, where are our hover-boards!?]])
*** [[http://www.bbc.co.uk/news/technology-33785285 Here]]
*** "WordOfGod" has it that an over-the-top, comedic portrayal of the future was deliberate, as productions of this type inevitably date.
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[[folder:And notably avoids...]]
* AllGuitarsAreStratocasters:
** Marty plays a Gibson ES-335 at the Enchantment Under The Sea Dance. Unfortunately, [[AnachronismStew this guitar was first made in 1958, three years after the year Marty has traveled to]]. (Note this is not Marty's guitar which he plays in 1985, it's the guitar he borrows from the Starlighters.)
** Also averted with Marty's yellow Erlewine Chiquita guitar at the beginning of the movie, and the black Ibanez 440-[=RS1=] he plays at his band's audition.
* MeanwhileInTheFuture: Once Marty goes to a time period, we stay there with him and don't see any changes he's made to the timeline until he gets back and sees them himself.
* NoNewFashionsInTheFuture: Although the clothes Doc Brown gives to Marty in Part II look almost exactly like his regular clothes, except that it's electronic and automatically adjusts its size. Doc also mentions that it's become a fad among young people in 2015 to wear their pockets inside-out, and suggests that Marty do so in order to blend in.
* OneSteveLimit: There are three guys named "Joey" in the trilogy: [[http://backtothefuture.wikia.com/wiki/Joey_Baines Marty's uncle]], [[http://backtothefuture.wikia.com/wiki/Skinhead one of Biff's cronies]] (nicknamed Skinhead), and [[http://backtothefuture.wikia.com/wiki/Joey_%281885%29 the bartender's assistant]] in Part III.
* OnlyChildSyndrome: Both Marty and Lorraine have numerous siblings that aren't that important to the plot, and of course Doc and Clara have two children together. George and Jennifer are only children, however. As far as we know, anyway -- we never actually met George or Jennifer's family. In the novel, we meet George's family and it is implied he is an only child.
* PoliticallyCorrectHistory:
** In Part I, Lou quips, "A colored mayor? [[ItWillNeverCatchOn That'll be the day]]" when Goldie Wilson muses after Marty tells Goldie that he will be mayor in 1985.
** After locking Marty in the trunk, one of Biff's gang calls one of the Starlighters a "spook", which is a largely forgotten racial epithet for a black person. In kind, the band members respond by calling him "peckerwood", which was likewise a racial slur for a white person.
** In Part 3, one of the old timers sees Marty in his hideous outfit and says "Must'a got that shirt off'n a dead Chinee..."
* RetroactivePreparation: Apparently does not work. (If it did, after Marty got stuck in 1955, his future self would have popped in with some plutonium, easy-peasy, problem solved. Ditto 1885 and a gallon of gas.)
* SanDimasTime: "If only I had more time... wait a minute, [[DefiedTrope I have all the time I want; I've got a ]]''[[DefiedTrope time machine!]]''" Marty then proceeds to screw it up by [[spoiler:giving himself only a few extra minutes, thus allowing him to make it back to the mall parking lot just in time to see Doc get shot]]. {{Justified|Trope}} in that he hadn't counted on the starter for the [=DeLorean=] failing. Again.
* WhatYearIsThis: Marty looks at {{newspaper|Dating}}s instead. And of course, the [=DeLorean=] has a bright digital display that tells you ''exactly'' when you are.
* YouAlreadyChangedThePast:
** Although Doc's letter at the end of Part 2 sort of plays this trope straight (the only part of the Trilogy to do so), though RuleOfCool applies for obvious reasons. This is debatable however, as since the letter arrives after the DeLorean gets struck by lightning, it could be argued that the Western Union guy wasn't there at all until the ripple effect kicked in.
** The 1955 Doc averts this. He specifically sends Marty back to a point ''after'' 1985 Doc has left the letter with Western Union. As can be seen in ''Part III,'' they didn't do anything about it, which allowed for normal 70+ year delivery: "and the Western Union guy lost the bet!''
[[/folder]]
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