[[quoteright:350:http://static.tvtropes.org/pmwiki/pub/images/4455024128a0484d0d9ac010.L.jpg]]
[[caption-width-right:350: [[SugarWiki/AwesomeMusic Taa-ta-ta-ta-ta-ta-taaaaaa!]]]]

->'''Marty [=McFly=]:''' Wait a minute, wait a minute, Doc...are you telling me you built a ''time machine''... out of a [=DeLorean=]?!\\
'''Doc Brown:''' The way I see it, if you're gonna build a time machine into a car, why not do it with some style?

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.

In ''Back to the Future'', Marty [=McFly=], a teenager from 1985, accidentally sends himself to 1955 in the time machine [[TheProfessor Doc Brown]] built out of a [=DeLorean=], and requires [[PlotCoupon 1.21 gigawatts of power]] to return home. After initial confusion, the 1955 Doc Brown agrees to help Marty get back home [[LightningCanDoAnything by striking his car with 1.21 Gigawatts of lightning]], giving Marty a week to [[GrandfatherParadox make his parents fall back in love at a dance]] and put bully Biff Tannen in his place. [[LateArrivalSpoiler He does it]], and in the process [[TemporalParadox invents rock 'n' roll and skateboarding]].

The sequels have their own pages:

* ''Film/BackToTheFuturePartII''
* ''Film/BackToTheFuturePartIII''

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]], [[Pinball/BackToTheFuture a pinball game]], [[TabletopGame/BackToTheFuture a card game]], a cinematic re-release in 2010 (to celebrate the 25th anniversary), and several spinoff products.

%% The tropes that a work named is trivia and belongs on the Trivia tab.
----
!!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
* AllThereInTheScript
** The names of the goons from Biff and Griff's gangs, as well as Lorraine's friends. The most easily recgonizable 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.
* ArtisticLicensePhysics: They're time travelling. 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 even the conditions in '''the centre of the Sun''' are only capable of producing hydrogen-to-helium fusion in RealLife.
* 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 Libyan's 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.
* 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 manipulate 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's 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.
* 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.
* 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 hoverboard: 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 month's 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 hoverboard) 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 gunbelt 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 to ''Film/TheTimeMachine1960''. 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.
** 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.
* 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]].
* 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.
* CoolOldGuy: Doc Brown
* 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.
* 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.
* 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.
* 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 a-1985!
** 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).
* [[FourTemperamentEnsemble Five-Temperament Ensemble]]: Biff (choleric), Clara Clayton (melancholic), Jennifer and George (phlegmatic), Lorraine and Doc (phlegmatic/sanguine), Mr. Strickland (choleric/melancholic), and Marty (sanguine).
** The [=McFly=] Family: Lorraine (phlegmatic/sanguine), George (phlegmatic), Dave (choleric), Linda (melancholic), and Marty (sanguine).
* 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.
* GenerationXerox: Many examples.
* {{GASP}}: Doc Brown. Doubles as an ActorAllusion for Creator/ChristopherLloyd who has done it in several other movies.
* 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 hoverboard. 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.
* 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=] stuck 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]].
* 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.
* ImmediateSequel: ''Part II'' and ''III'' literally begin seconds after the previous ones, ''II'' after ''I'', and ''III'' after ''II''.
* 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.
** 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.
* {{Jerkass}} / 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 moreso than his future offspring Griff.
* TheLawOfConservationOfDetail: The first twenty minutes or so of ''Part I'', as well as 2015 [=McFly=] house portion of ''Part II''.
* 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, sweet justice.
* 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. 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.
* 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.
* 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 ''Film/BackToTheFuture'''s 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.
* 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-travelling 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''...)
* 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 estabilishing shot of Hill Valley...
** 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... Hoverboard?"]], 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:
** 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 hoverboards...[[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.
** 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.
** A copy of ''USA Today'' is featured prominently as a RippleEffectIndicator in ''Part II''.
** "[[AC:[[ComputerVoice 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 Jewlery 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 bech 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!
* 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
* 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: Doc and Marty throughout the trilogy.
* 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 a dream. 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 high noon 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 hoverboard 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 a plutonium-powered fission reactor kinda wouldn't generate any power whatsoever.
* 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''.
* 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.
* 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 "[[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
* 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, 18 years old. Do the math, and you see he was born in 1913. This makes him 42 in 1955 and 72 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 hoverboards!?]])
*** "WordOfGod" has it that an over-the-top, comedic portrayal of the future was deliberate, as productions of this type inevitably date.
[[/folder]]

[[folder:Part I]]
* AluminumChristmasTrees:
** In-universe. 50s Doc initially takes this approach towards a [[UsefulNotes/RonaldReagan Reagan Presidency]], but comes around to it when he sees Marty's portable television studio (read: a camcorder), realizing that the President has to look good on TV.
** As Marty tries to tell George to ask Lorraine to the dance, George objects by saying it would mean missing his favorite TV show ''Science Fiction Theatre''. ''Science Fiction Theatre'' was an actual sci-fi show from the 50s, a spiritual predecessor to ''Series/TheOuterLimits1963'' and ''Series/TheTwilightZone'' (in the extended version of the "Darth Vader" scene, Marty also name-drops those shows).
* AsLongAsItSoundsForeign: The Libyan terrorists speak vaguely Arabic-sounding gibberish.
* AttemptedRape: Biff with Lorraine in 1955.
* AutoErotica: Marty's plan to get his parents together involves George finding him "parking" with Lorraine and trying [[DateRapeAverted to take advantage of her]], then pulling him out of the car and pretending to beat him up to make him look like he's the tougher guy. Except Biff turns up instead of George, and he wants revenge on Marty for the $300 damages his car took in the manure truck incident, so he decides to attempt to molest Lorraine. Hence, George's "rescuing" Lorraine ends up becoming the real deal.
* BeenThereShapedHistory: Back in 1955, Marty [=McFly=] plays Chuck Berry's ''Johnny B. Goode'' when he steps in for Chuck's cousin, Marvin Berry. While Marty is playing, Marvin calls Chuck up so he can listen in on this "new sound." He also gives the 1985 mayor Goldie Wilson, at that time the black janitor in the malt shop, political aspirations the exact year the Civil Rights Movement started.
* TheBigDamnKiss: George and Lorraine at the dance, complete with "Earth Angel" swelling on the soundtrack, and saving their son's entire ''existence''.
* BigNo: Marty after Doc is shot by the Libyans.
* BlatantLies: Lorraine says to Marty that she never went chasing after boys. When we see her younger self, it turns out that she is instantly enamored with George and, due to Marty taking his dad's place due to an accident, all but attempts to force herself on him.
* BorrowedCatchphrase: "If you put your mind to it, you can accomplish anything." Doc never actually says it in the movie (or the rest of the trilogy), but Jennifer attributes it to him. Only Marty and George ever say it -- in fact, it seems that George has adopted it as his own catchphrase at the end of the movie.
* BrotherSisterIncest: {{Invoked}}. Lorraine is coming hard onto Marty, kissing him back into a corner, and it suddenly occurs to her that it's like kissing her brother. She is {{Squick}}ed, although not ''nearly'' as much as Marty is, knowing that it's really ParentalIncest.
* BuffySpeak:
-->'''Marty:''' Time circuits, on. Flux capacitor... fluxing.
* TheCameo: Huey Lewis is the teacher who tells Marty [[CastingGag that his music was "too darn loud"]].
* CastingGag: Huey Lewis, playing the audition judge in 1985, tells Marty's band that they're "just too darn loud." [[HypocriticalHumor The band was playing Lewis' own song, "The Power of Love."]]
* CelebrityParadox: Huey Lewis exists in the ''BTTF'' universe, as proven by Marty's posters in his room -- and so does the audition judge, played by... Huey Lewis. Even better: at the end of the movie, Marty's clock radio plays "Back in Time" by Huey Lewis and the News. The song was specifically written for (and contains a TON of references to) a little movie called ''Back to the Future''.
* CessationOfExistence: Self explanatory and adverted. Marty inadvertently creates a paradox when he interfered with his parents' meeting in 1955. This slowly erases the existence of his brother Dave, his sister Linda, [[OhCrap and then himself]]. It's averted at the last moment, when his father George kisses his mother Lorraine at the dance, [[SetRightWhatOnceWentWrong thus resolving the paradox and ensuring a happier future]].
** This may explain why Marty [[JustifiedTrope didn't cease to exist straight away]]. By giving him "borrowed time" the universe was trying to correct its own paradox.
** There is however, a worrying implication if Marty did cease to exist proper. If he had never been born, ''how could'' he go back to 1955 to interfere with his parents' meeting in the first place? [[TimeCrash His demise could have potentially compromised all of reality]].
* ChekhovsBoomerang: Marty's radiation suit.
* ChekhovsGag: The joke about the [=TV=] show they're seeing at the Bates' house in 1955. It's seen earlier at [=McFly=]'s house in 1985, and as Marty watches the same episode in 1955, he notes that he's seen it and it's a classic, to which one of his uncles replies that it's brand new and it's impossible that he could have seen it. Marty says he saw it on a rerun, prompting more confusion from them.
* ChekhovsGun
** At the start of the film, Marty is conveniently given a flyer by a woman who (along with other volunteers) is attempting to raise money to save the historic clock tower. The scene is played for laughs, but the flier contains crucial information on how to return to the future, including the exact date and time that the clock tower was struck by lightning.
** Lorraine tells the kids that if her father hadn't hit George [=McFly=] with his car in 1955 before the dance, none of the kids would've been born. She also says that she and George fell in love after they had their first kiss at the dance. It looks like it's just informing us about how the romance has gone out of their marriage. It's not.
** When Marty hides the [=DeLorean=] shortly after arriving in 1955, he is shown putting the walkman he later uses as part of his alien impersonation in the car for no other reason than to establish he has it.
** Ironically for a light-hearted action comedy, the film is often used in film studies as a perfect example of this trope, since virtually every single thing that happens in the film exists to set up a later event.
* ChekhovsGunman: Dixon, the guy who cuts in on George and Lorraine at the dance, was previously seen kicking George around when he had the [[KickMePrank "Kick Me" sign]] on his back.
* ChewingTheScenery: Surprisingly, Marty - near the end of "Johnny B. Goode". His faces while he goes over-the-top are hysterical.
* CleanUpTheTown: Goldie Wilson, in 1955 a busboy at Lou's Diner, imagines himself as doing this after Marty recognizes him as the future mayor and tells him that. Lou hands him a broom and tells him he can start by sweeping the floor.
* ClockDiscrepancy:
** Marty is at Doc Brown's house, and thinks he will be on time for school, only to discover all his clocks are twenty-five minutes slow.
** Doc Brown proves to Marty that the time machine works by syncronizing watches with a digital clock he attaches to his dog, then sending the dog one minute into the future. When the dog shows up again, his clock is a minute slower than Doc's.
* ClownCar: Biff's goons make the mistake of insulting one of The Starlighters outside his Cadillac, causing four others to exit the car.
* CombatPragmatist: Marty has no problem sucker-punching Biff.
* ComicallyMissingThePoint: Played with, perhaps. It initially sounds as if Marty is amazed by the time machine. Then he adds the phrase, "out of a [=DeLorean=]?!"
-->'''Marty [=McFly=]:''' Are you telling me you built a ''time machine''... out of a [=DeLorean=]?!
** In 1955, when Marty tells Doc who he is while using the mind-reader:
-->'''Marty:''' Doc, I'm from the future. I came here in a time machine that you invented, and I need your help getting back to the year 1985.
-->'''Doc:''' My God... Do you know what this means? It means that ''this damn thing doesn't work at all!''
* CommonKnowledge: In-universe example, when Doc Brown is showing Marty how to set the target date on the time machine:
-->'''Doc Brown:''' Say you wanted to see the signing of the Declaration of Independence." (sets date to JUL 04 1776)
** The Declaration was not signed on this date.
-->'''Doc Brown:''' Or witness the birth of Christ!" (sets date to DEC 25 0000)
** Jesus would not have been born in December. Plus "0000" isn't even a year on any calendar (the year before AD 1 was 1 BC). Both of these were intended as ''[[ViewersAreGeniuses jokes]]'' [[ViewersAreGeniuses by the filmmakers]] who knew full well that neither of these dates were accurate. [[ViewersAreMorons Nobody got it]].
*** The {{novelization}} had Doc attempt to rationalize the latter date:
--->'''Doc:''' Of course, there's some dispute about that date. Some scholors say Christ was born in the year 4 B.C. and that somebody made a mistake in what year it was during the Dark Ages. But assuming 12-25-0 is correct, all we'd have to do is find our way to Bethlehem.\\
'''Marty:''' No sweat.
* ContrivedClumsiness: Marty "accidentally" trips Biff when they're in the diner in 1955 Hill Valley.
* ConvenientSlowDance
* CoolOldGuy: Curiously, Biff!2015. He's a lot more relaxed and mature, even chuckling at things that were previously embarrassing for him.
* DamselInDistress: Invoked and then played straight -- Marty's plan is to stage an AttemptedRape of Lorraine ([[{{Squick}} his own mother]]) so that George can intervene and win Lorraine's affections. However, when Biff interrupts the staged attempted rape and tries to actually rape Lorraine, it's up to George to save the day, which he does, achieving the desired result.
* DateRapeAverted: {{Invoked}} with EngineeredHeroics, then [[DoubleSubversion doubly subverted]]: Biff interferes with Marty and Lorraine's [[UnusualEuphemism activities]], and George winds up interfering with Biff's [[UnusualEuphemism activities]] -- [[MomentOfAwesome successfully]]!
* DeathGlare: Marty gives one to Biff after stopping him from attacking George by [[ContrivedClumsiness tripping him up]] - which almost immediately turns into a hilarious OhCrap when he realizes that Biff is [[DavidVersusGoliath twice his size]].
* DelayedRippleEffect: Marty has a week to get his parents together before he'll be erased from existence.
* DidYouJustPunchOutCthulhu: Everybody is stunned that Biff gets beaten by George.
* DiesWideOpen: Subversion, towards the end.
* DisneyDeath: Doc Brown in the revised timeline.
* DivingSave: Marty pushes George out of the way of Lorraine's father's car, by accident.
* DysfunctionalFamily: George and Lorraine at the beginning of the movie.
* EasilyForgiven: While Biff in the altered timeline appears to have become a harmless, eager-to-please GentleGiant who is barely recognisable as the bully he used to be, both George and Lorraine seem to be remarkably grudge-free about him trying to rape Lorraine.
* EatingLunchAlone: George in 1955 tends to eat by himself in the cafeteria and focus on writing his ideas for a science fiction book down on paper.
* EngineeredHeroics: Subverted: Marty's plan to get George and Lorraine together goes wrong, requiring George to be a real hero.
** In the {{novelization}}, George worries that Biff was in on the plan and had faked being knocked out, until Marty confirms that Biff was serious.
* EverythingsBetterWithCows: After Marty ends up in 1955, he runs into a scarecrow, then crashes into the barn where Old Man Peabody's cows reside.
* EvilRedhead: "Dixon", the [[EvilLaugh cackling]] punk who cuts in on George's dance with Lorraine.
* ExactWords: George won't try to ask Lorraine to the dance, telling Marty "neither you nor anybody else on this planet is going to make me change my mind." So that night, Marty pretends to be "Darth Vader, an extra-terrestrial from the planet Vulcan".
* FalseStart: George with Lorraine in 1955.
* FirstKiss: George and Lorraine have theirs during the Enchantment Under The Sea Dance, while the band plays "Earth Angel". (Marty has to fill in for a band member who injured his hand to ensure that it happens).
* FeetFirstIntroduction: Marty. You don't even get to see his face until a minute and a half later.
* FiveFiveFive: Doc Brown's phone number, as well as Jennifer's grandmother's.
* FlorenceNightingaleEffect: DiscussedTrope. How Marty's mother fell in love with his father... and how Marty accidentally ends up replacing his father in her affections. [[{{Squick}} Squicks]] Marty, repelling him, and inadvertently making him even more attractive to her. Especially after he defends her from Biff in the school lunch room. Lampshaded by Doc.
* {{Foreshadowing}}:
** Among many things, Doc commenting on how Marty's 1985 photo is obviously a forgery, since his brother's hair is missing.
** One of the clocks seen at the start of the film shows a man hanging off of the minute hand. Doc is later hanging off the clock tower face towards the end of the film. Also, the clocks are slow, with Marty being told of this, which sets up that he is going to go back in time later.
** Marty's skateboard at the beginning hits a case of plutonium when Marty enters the garage. [[spoiler:As revealed later, Doc had stolen it from the Libyans who later shoot him dead]].
** Marty hitches a ride on the back of a Jeep in 1985 on his way to school. He later does the same thing in 1955 when he is chased around the town square by Biff and his thugs.
** The following exchange at the beginning:
-->'''Strickland:''' ow let me give you a nickel's worth of free advice, young man. This so-called Dr. Brown is dangerous. He's a real nutcase. You hang around with him, you're gonna end up in big trouble. [...] No [=McFly=] has ever amounted to anything in the history of Hill Valley!\\
'''Marty:''' Yeah, well, history is gonna change.
** Lorraine says to her children at the dinner, "I think it's terrible. Girls chasing boys. When I was your age, [[ParentalHypocrisy I never chased a boy, called a boy]] or... [[BlatantLies sat in a parked car with a boy]]." Considering her behavior around Marty in 1955....
** Upon being rejected for the Battle of the Bands, Marty says "I'll never get to play in front of anybody..." Guess what Marty does at the dance in 1955?
** The [=McFly=] family are watching the episode of ''The Honeymooners'' where "Ralph dresses up as the man from space". The Baines family in 1955 watch the same episode when Marty is with them. It also sets up Marty being mistaken for a "man from space", first of all in front of the Peabodys when Marty first arrives in 1955 [[spoiler:and later when he turns up in George's bedroom to coerce him to take Lorraine to the dance]].
** Doc recalls in the Twin Pines Mall parking lot how Old Man Peabody owned the area the mall is built on. Marty encounters him and his family upon first arriving in 1955, and during the encounter with the Peabodys, Marty runs over one of the two pine trees. It was Twin Pines Mall at first, but it is Lone Pine Mall at the end of the film.
** When Marty gets to 1955 and crosses the street in front of the movie theater in the town square he is nearly hit by a car. Guess what happens a few scenes later?
* FormerTeenRebel: Lorraine
* FreezeFrameBonus: In the first movie, 1955-Doc has no less than ''four'' separate watches (one's even built into his clocktower model as the clock).
* FromTheMouthsOfBabes: "He's mutated into human form! Shoot him, Pa!"
* FunHatingConfiscatingAdult: Strickland. His name is probably an inside joke on the word '''strict'''.
* FunnyBackgroundEvent
** Stella keeps removing Milton's coonskin hat while Marty is taking in the surroundings of the Baines' dining room.
** When Biff says "Make like a tree... and get out of here", one of his goons turns his head towards him, and [[EyeTake his eyebrows slowly try to crawl their way up to his hairline]].
* GaleForceSound: Marty hooks up an electric guitar to a [[UpToEleven ludicrously huge speaker]]. He plays a single chord and is physically hurled backwards by the sound (the speaker is destroyed in the process).
* GarageBand: Marty [=McFly=]'s band, the Pinheads, which auditions for the Battle of the Bands competition.
-->'''[[Music/HueyLewisAndTheNews Audition Judge]]:''' Hold it, fellas. I'm afraid you're just too darn loud.
* GettingCrapPastTheRadar:
** Biff, when he sits at Lorraine's table and tries to grope her: "You want it, you know you want it, and you know you want me to give it to you."
** During the scene where Marty and George are going over the plan of how they're going to get George with Lorraine we have this exchange while George is doing his family's laundry:
-->'''Marty:''' Because George, (''voice begins to stutter'') nice girls get angry when guys take advantage of them.\\
'''George:''' Hoh! You mean you're going to touch her on her-- (''holding a bra in his hand'')
** When Strickland gives Jennifer her tardy slip, she holds it up between fingers, her middle finger very prominent.
* GodGuise: Marty uses his radiation suit and Walkman stereo to dress up as "Darth Vader from the Planet Vulcan". He frightens George and threatens to [[CutHisHeartOutWithASpoon melt his brain]] if he doesn't take Lorraine to the school dance.
* GrumpyOldMan: Sam Baines really isn't that happy with Marty jumping in front of his car.
* HereWeGoAgain: The ending was supposed to be this trope as they'd never planned any sequels. The film's main problem (that Marty accidentally erased himself from history) resulted because he used the time machine; just when everything is perfect, Doc arrives and whisks them off in it again.
* HeroicSacrifice: Doc draws the Libyans' attention to give Marty time to run, and gets shot for it.
* IKnowWhatWeCanDoCut: Marvin Berry declaring that the school dance is officially over -- unless Marty "knows ''someone else'' who can play a guitar?" Cut to Marty on-stage.
* ImperialStormtrooperMarksmanshipAcademy: The Libyans manage to hit everything ''but'' the [=DeLorean=] with their sprayed gunfire. That's [[JustifiedTrope justified]] since the Libyans are using [=AKs=] and not even bothering with short bursts. [[RealityIsUnrealistic Nevermind that any unbraced weapon fired on full-auto will never make their mark]]. Also subverted: when they fire at Doc, they do kill him. [[spoiler:Only the first time, though. The second time, he takes Marty's advice and puts on a bulletproof vest which saves his life]].
* ImprovisedLightningRod: Doc Brown uses the Clock Tower as a lightning rod to gain the 1.21 gigawatts of electricity the [=DeLorean=] needs to get back to the future.
* ImprovisedZipline: Doc Brown uses the heavy duty electrical cable attached to the clock tower as a line to reach the ground quickly and fix a break in the line.
* IncestIsRelative: Parodied, in that whilst Marty knows who Lorraine really is, she has no idea as to his true identity. Luckily for Marty, Lorraine likens kissing him to kissing her brother.
* InSpiteOfANail: Played with. The new 1985 is identical in most respects... but not entirely. The [=McFly=] family turned out differently, Biff Tannen turned out differently, Hill Valley's shopping is now done at the ''Lone'' Pine Mall, and of course, Chuck Berry got the idea for "Johnny B. Goode" from a sample he overheard during a telephone call from his cousin Marvin.
* IShouldWriteABookAboutThis: And indeed, George does, based on "Darth Vader" visiting him at night in 1955.
** One hopes that Gene Roddenberry didn't get sued in 1966, or George Lucas in 1978, for stealing ideas from George's first novel!
** In the {{novelization}}, while Marty visits Doc after visiting George's house for the first time, Doc remarks, "If you get back, maybe you could make a movie out of this."
* ItWillNeverCatchOn
** "Ronald Reagan? The ''actor''?"
** "Hey, Biff, get a load of this guy's life preserver! Dork thinks he's gonna drown!"
* IWasQuiteALooker: Lorraine at the beginning of the movie.
* JustKeepDriving: Used as a one-off joke when Marty escapes Old Man Peabody's farm and steps on the entrance to the construction site for Lyons Estate (which is breaking ground next winter). After attempting to ask a passing middle-aged couple where he was, the woman starts to freak, tapping her husband rapidly on the shoulder and yelling '''"DON'T STOP, WILBER! ''DRIIIIIIIVE!!!"''''' Marty then has to use the billboard advertising the new development to hide the [=DeLorean=].
* TheKeyIsBehindTheLock: Marty gets locked in a car trunk, along with the keys to the trunk.
* KeyUnderTheDoormat: Doc Brown is not particularly security conscious.
* KickMePrank: George is the victim of one at school.
* KidFromTheFuture: Marty, although his parents know nothing of who he really is. Lorraine is enamoured with him due to his cavalier attitude (and the "Florence Nightingale effect") and George initially thinks he's a pushy pest who keeps following him around.
* LateForSchool: Marty, for the fourth time in a row.
* LetsGetDangerous: Bumbling fretful Doc, when he sees that he accidentally unplugged the ''other'' end of the cable, sucks it up, and ziplines off the clock tower in the middle of a storm.
* LettingTheAirOutOfTheBand: Happens the minute Biff angrily marches in to throw George out of the diner. Apparently, someone in the room had a good sense of dramatic tension to unplug the jukebox at that ''exact'' moment.
* LimitBreak: George punching out Biff after Biff laughs at him and pushes Lorraine to the ground.
* LoopingLines: Crispin Glover (George [=McFly=]) lost his voice due to nervousness while filming Back to the Future. For some scenes, he had to silently mouth his lines, with his voice being dubbed in later at a recording studio.
* MaltShop: Lou's Diner
* ManlyTears: Marty towards the end of the movie. After seeing his friend, Doc, killed once, Marty is now praying that Doc read his letter and took precautions so he wouldn't be killed a second time. Marty arrives just in time to see the Libyans shoot Doc again. Running over to him, Mary finds Doc unconscious. Assuming the worst, he begins sobbing. However, we find out that Doc is fine. Marty's tears of sadness soon turn to tears of joy.
* MassOhCrap: '''''[[VisualPun "SHIIIIIIIIIIIIIIIIIIIIIIIIT!!"]]'''''
* MeaningfulEcho: The instance here is George and Biff's conversation after Biff wrecks a car George loaned him:
-->'''Biff Tannen:''' ''(playing George's head like a bongo)'' Hello? '''''Helloooooo?!''''' Anybody home?! Think, [=McFly=]! Think! I've gotta have time to get 'em retyped. Do you realize what would happen if I hand in ''my'' reports in ''your'' handwriting? I'll get fired. You wouldn't want that to happen, would ya? ''[pulls on George's tie]'' Would ya?
-->'''George [=McFly=]:''' Well no, of course not, Biff. I wouldn't want that to happen. ''[Biff helps himself to some gumballs]'' Now look, I'll uh, finish those reports on up tonight, and I'll run 'em on over first thing tomorrow. All right?
-->'''Biff Tannen:''' Not too early. I sleep in Saturday.
** Likewise, Marty walks into Lou's Diner and after Lou hands him a cup of coffee, the camera pans to show that Marty is sitting next to George, who is occupied eating his breakfast. Suddenly the doors fly open:
-->'''Biff Tannen:''' ''(again with the head-battering)'' Hello? '''''Helloooooo?!''''' Anybody home?! Think, [=McFly=]! Think! I gotta have time to recopy it. Do you realize what would happen if I hand in ''my'' homework in ''your'' handwriting? I'll get kicked out of school. You wouldn't want that to happen, would ya? ''[George hesitates. Biff grabs George by his shirt]'' Would ya?
-->'''George [=McFly=]:''' Well no, of course not, Biff, I wouldn't want that to happen... I'll, uh, finish that on up tonight and then I'll, uh, bring it over first thing tomorrow morning.
-->'''Biff Tannen:''' Not too early. I sleep in Sunday.
* MeetCute: George and Lorraine's first meeting, the way it originally happened.
* MomentKiller: Marty and Jennifer are playfully flirting in the courthouse square, and are an inch away from kissing...when they are interrupted by: "Save the clocktower! ''Save the clocktower!''", complete with the lady shaking the donations tin in their faces. So much for that moment....
** And as George is stumbling his way in wooing Lorraine at the cafe, it seemed like he'd succeed until Biff showed up.
* MundaneMadeAwesome: George's method of [[BarSlide ordering a milk]]....chocolate. The outtake is even better, where the milkshake glass bounces off George's hand and crashes to the floor.
* MyCarHatesMe: The Libyan's VW bus.
-->"Rrrgh! Damn Soviet gun!"\\
"Gah! Damn German car!"
** And of course, the [=DeLorean=].
* NaughtyBirdwatching: When George is spying on Lorraine in 1955. Lorraine in the original 1985 even refers to the event as birdwatching.
* {{Nerd}}: George, although Marty's intervention via time travel turns him into a much ''cooler'' class of nerd.
* NeverMyFault: Biff berates George for the auto accident he got into after basically admitting he was drinking and driving, ''and'' he complains about George's choice of beer afterwards.
* NextSundayAD: The film was released on July 3, 1985, but set nearly 4 months later on October 25-26, 1985.
** In the DVD commentary, it was said that people actually showed up at Puente Hills Mall, the location used for Twin/Lone Pine(s) Mall, on October 26, 1985 at 1:18 AM to see if anything would happen.
* NiceJobFixingItVillain: Biff pushing Lorraine down and [[EvilLaugh laughing about it]] gives George the [[DateRapeAverted resolve he needs]] to punch him out.
* NoAccountingForTaste: George and Lorraine in the original 1985, at the start of the film.
* NoodleIncident
** Marty setting fire to the living room rug at the age of eight.
** Also, it's briefly implied that Marty and George [=McFly=] aren't the first victims of a Sam Baines hit-and-run accident, given that the moment George rides away on his bike, Sam shouts, "'''''Stella!''''' Another one of these damn kids jumped in front of my car! Come on out here and help me bring him in the house!"
* NostalgiaAintLikeItUsedToBe: Compare the film's portrayal of 1955 with that of 1985. On the other hand, the film does a good job in showing both the bright, sunny veneer of TheFifties and the darker, less pleasant aspects underneath without being bluntly {{Anvilicious}}.
** When Marty arrives in the 1955 town square, we can see some of the things that have and haven't changed since then. The Texaco station has a team of four uniformed men to service cars, including filling the tank and polishing the engine. Also, much like the 1985 town square has a mayoral campaign van going around blaring "Re-elect Mayor Goldie Wilson!" on loudspeakers, the 1955 version of this scene has a car blaring "Re-elect Mayor Red Thomas!" on loudspeakers, even decked out with similar looking signs.
* OhCrap
** "They found me. I don't know how, but they found me. '''''Run for it, Marty!'''''"
** Marty goes wide-eyed after tripping Biff up in the diner, seeing how much bigger Biff is than himself.
** [[http://26.media.tumblr.com/tumblr_kugf95XVXN1qzvqipo1_500.jpg The look on Doc's face]] when his return home simulation fails spectacularly (and causes some rags to catch fire) is utterly priceless.
** The look on George's face when he discovers it is Biff, not "Calvin", in the car with Lorraine.
** Biff's thugs when the rest of the band members get out of the car [[spoiler:they just dumped Marty in the trunk of]] on the night of the dance.
** Biff, when he sees in George's face that he's pushed him too far and a left hand is coming his way.
** Marty gets a huge one at the dance when he starts to fade out of the photograph, and sees his right hand start to fade away.
* OedipusComplex: Averted. Marty is understandably squicked by young Lorraine, his future mother, being amorously infatuated with him and desperately tries to hook her up with his dad instead so he won't cease from existence. He was planning to fake AttemptedRape on her so his father could come to the rescue, but luckily, he didn't have to go through with that plan as George punched out Biff instead, who was trying a real rape attempt on her.
* OOCIsSeriousBusiness: Doc is surprised and asks for confirmation when Marty mentions that [[TookALevelInBadass George stood up to Biff, for the first time ever]]. This is a subtle hint about Doc realizing that the status quo timeline has been deeply changed already so reading Marty's letter would be now a less game-breaker thing for him.
* ParentalBonus: After Marty wakes up from being hit by Lorraine's father's car, Lorraine tells him that his pants are "over there... on my hope chest". Many people who were born after the 1950s may not understand what a hope chest is. It's a chest that young girls used to keep in preparation for their marriage. In other words, Lorraine is already fantasizing about marrying the young man that she does not realize is her future son. One assumes that in the original timeline, this also happened with George.
* ParentalIncest: Marty [[{{squick}} seriously]] tries to avert this trope, and does everything wrong until the night of the party; everything he does only makes him more attractive to her. He jumps and flees when she makes a pass at him, defends her from Biff's "meat hooks", trips up Biff when Biff goes after George, and leads Biff on an over-the-top skateboard chase culminating in Biff's comeuppance in manure. By this time, she ''really'' wants to get to know him.
* ThePeepingTom: The then-teenage George [=McFly=] spies Lorraine undressing from a tree next to her window. This becomes a crucial plot point as this is the point where Marty alters history. When George falls out of the tree, Marty pushes him out of the way of an oncoming car... accidentally preventing his parents' original meeting. For an idea of how it originally happened, imagine Marty's actions that night at the dinner table with George in place of Marty.
* PetsHomageName: Doc's dogs. His 1985 dog is named Einstein, his 1955 dog is Copernicus.
* PlotBasedVoiceCancellation: When Marty tries to tell Doc about the future while the latter is on top of the clock tower:
-->'''Marty:''' ''(shouting at Doc)'' On the night I go back in time, you will get-- ''(the clock sounds its bell, drowning out Marty and startling Doc)''
* PoliceAreUseless: Aside from AttemptedRape above, Biff in 1955 also makes multiple threats of assault throughout the movie, and in one scene attempts to commit MURDER, and nobody even seems to think that he's doing anything illegal.
* ThePowerOfRock: Played with. Marty's rendition of "Johnny B. Goode" impresses everybody until he gets carried away with his guitar solos.
-->'''Marty:''' I guess you guys aren't ready for that yet... but your kids are gonna love it.
* PrecisionFStrike:
** "If my calculations are correct, when this baby hits eighty-eight miles per hour...you're gonna see some serious ''shit''."
** One word: '''[[VisualPun SHIIITTTTTTT!!]]'''
* PrinceCharmingWannabe: Biff with Lorraine.
* PronounTrouble:
-->'''Marty:''' (''shouting'') Hey, Dad! George...! You on the bike...!
* PsychoStrings: The musical score gets screechy as Marty fades from existence.
* PunchSpinGape: Biff catches one of these in the end.
* QuipToBlack: "Roads? Where we're going, we don't need [[GlassesPull roads]]."
* RealityIsUnrealistic: Some people complain that Michael J. Fox's [[NonSingingVoice singing double]] is a bit too low for Marty's character during his performance of "Johnny B. Goode". However, it's pretty common in RealLife for somebody's singing voice to sound radically different than their speaking voice -- see SingingVoiceDissonance for examples.
* ReliablyUnreliableGuns: Marty is saved repeatedly from being shot by Libyans because their rifle jams. They are shooting an AK-47, which are famed for their reliability even under the harshest conditions. However, we do see them simply trying to clear the jam rather than abandoning the gun immediately.
* RejectionAffection: Lorraine with Marty.
* RetGone: Dave, Linda and Marty in the photograph.
* RetroactivePrecognition: "That's right, he's gonna be mayor!"
* RewindReplayRepeat: "They found me... I don't know how, but they found me... '''''Run for it Marty!'''''" replayed by a Doc Brown who was told not to by Future Boy Marty.
* RightPlaceRightTimeWrongReason: Marty finding that George is a peeping tom.
* RippedFromThePhoneBook: When Marty is looking up Doc Brown's house in the phonebook, he tears the page out for reference.
* RockersSmashGuitars: Marty ruining the mood of his song by acting like a HeavyMetal singer.
* RunningGag: People mistaking Marty's down jacket as a "life preserver" - the guy behind the counter at the malt shop, or Lorraine's mother.
** Lorraine keeps calling Marty "Calvin Klein", even after Marty corrects her.
* {{Scary Black M|an}}en: "Who you callin' "spook", peckerwood?!" Biff's gang seems more afraid of the copious amount of pot smoke billowing out of the Starliters' car than anything else: "I don't wanna mess with no reefer addicts!"
* SeeminglyWholesomeFiftiesGirl: Lorraine, much to the horror of Marty.
* SequelHook: "Where we're going we don't ''need'' roads," and the [=DeLorean=] being flown at the camera. [[SincerityMode Completely unintentional, of course.]]
* SharedFamilyQuirks: Marty sits in a diner and nervously rubs the back of his head in disbelief that he's in the past, and the camera pans to show he's sitting next to George, who is doing the exact same thing.
* ShoutOut
** The farmer is Old Man [[WesternAnimation/RockyAndBullwinkle Peabody, and his son is named Sherman]].
** In Doc's lab in the beginning, the amplifier is labeled "CRM 114", which was the code name for a radio device from ''Film/DrStrangelove''.
** After Sam Baines hits Marty with the car, he yells [[Theatre/AStreetcarNamedDesire "STELLA!"]].
** While playing "Johnny B. Goode", Marty emulates other guitar heroes, duck-walking like Music/ChuckBerry, windmilling like [[Music/TheWho Pete Townshend]], and tapping like [[Music/VanHalen Eddie Van Halen]].
* SlowElectricity: Near the end of the film, the lightning crawls down the wire at roughly a walking pace.
* TheSlowPath:
** 1955 Doc regrets having to wait 30 years to talk to Marty about their adventures.
** Regarding Marty's attempts to warn him of his impending death, Doc insists that he'll find out through the ordinary progression of events.
* SoundtrackDissonance: "Mr. Sandman" by The Four Aces, a cheerful song, is used to underscore Marty's confusion as he arrives in the 1955 Hill Valley during the MisterSandmanSequence. Downplayed, as it represents the (apparent) clean, wholesome, optimistic, friendly [[TheFifties Fifties]] Marty found himself in.
* SpearCarrier: The couple at the dance amazed at George standing up for himself.
* StoppedClock: The clock tower stopped after being stuck by lightning, giving Marty and Doc a precise time to use the lightning to time travel.
* SweetAndSourGrapes: Towards the beginning, Marty admires a pickup truck, wondering what it'd be like if he had it. When he comes back from 1955, he discovers he has that truck (or another truck like it).
* TechnologyPorn:
** The [=DeLorean=] when Doc introduces it.
** Also the opening, showing off various gadgets Doc has at home.
* TheReasonYouSuckSpeech: Strickland really dishes it out to Marty at the beginning for being a "slacker", and to the rest of the [=McFly=] family as he drives his point home.
* TitleDrop:
** Doc declares he has to send Marty "Back! To the ''future!''"
** And again at the end of the movie when Doc comes back from 2015, to pick up Marty and go back to... you know.
* TookALevelInBadass: George standing up to Biff is a critical moment that fills him with self-confidence and changes the destiny of his whole life and family.
* TrustPassword: Marty tries several that don't work, such as who the President is in 1985[[note]][[ItWillNeverCatchOn Doc refuses to believe an actor could be President]][[/note]], and showing him a photo of his family with his sister in a Class of 1984 sweatshirt[[note]]Doc doesn't believe this once because unbeknownst to Marty, Dave's hair has started to disappear, making it look like it's been poorly doctored[[/note]]. What finally works is the story of how Doc got the (currently very fresh) bruise on his head, and the idea for the Flux Capacitor that came from it.
* TurnOutLikeHisFather: Played with in every possible way. People, especially Strickland, tell Marty he's going to be a [[LoserSonOfLoserDad loser like his dad]], then the past changes and his dad is not a loser but Marty is still destined to be a loser, then that future is possibly avoided presumably letting Marty succeed at a creative pursuit like his dad.
* VanityLicensePlate: The [=DeLorean=] has the tags OUTATIME. And really crappy screws holding it on the back of the [=DeLorean=], because of its habit of popping off and pirouetting on a corner.
** After the first plate falls off, Doc Brown goes into the future and replaces it with a 2015 barcode license plate with enough bars to spell "OUTTATIME", inserting another "T". That one also falls off when the entire car is pulverized by a freight train, and does its little pirouette trick again, likely the only bit of the car that survived the collision intact.
* VerbalBackspace: In the {{novelization}}, after his "When this baby hits 88 MPH, you're going to see some serious shit" line, Doc realizes that Marty is filming this and quickly rewords his statement without colloquial language:
-->"When a speed of eighty-eight miles an hour is attained, unusual things should begin happening in this phase of temporal experiment number one."
* WhatHappenedToTheMouse
** The Libyans. They come charging in, shooting at Doc Brown from the van, they hit a kiosk and the van tips over. Then Marty, Doc, and the film forget about them completely, even having a joyful reunion at the end without bothering to see what's going on with the homicidally angry terrorists in the van a few yards away.
** What happened to Doc Brown's remaining plutonium? Did he use it all before fitting Mr. Fusion, or did he just throw it in a bin somewhere? (Which, given the general recklessness he displays during the trilogy, is not that much of a stretch.)
** When Doc traveled to 2015, he took Einstein with him, but when he came back, Einstein was missing. In Part II, [[HandWave Doc tells Marty that Einstein was in a suspended animation kennel]] between the trips.
* WhosOnFirst: Marty's attempts to get a Tab, and then a Pepsi Free, at Lou's Cafe in the 50's.
-->'''Lou:''' You want a Pepsi, pal, you're gonna have to pay for it!
* YouKeepUsingThatWord: At least from 1955 Doc's point of view, as he thinks that Marty's use of the word "heavy" still applies to weight and measurements, when, from Marty's point of view, he's just using the slang term for something that has a deep, powerful impact, whether philosophical, intellectual, or emotional.
[[/folder]]

[[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
* 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? 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.
* TimeCrash: Doc is concerned that causing an unresolvable time paradox or having someone encounter his or her past self could potentially destroy the timeline.
* 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.
** 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]]
----