-Full Synopsis by uruseiranma-
After the lightning storm on November 12, 1955, Doc Brown (Christopher Lloyd awakes back at his family mansion with TV playing Hoody Doody, not quite sure how he got home. Doc swears that he may have seen a vision of Marty McFly (Michael J Fox) afterwards saying he had 'come back from the future,' but thinks he may have been hallucinating. This turns out to be a reality, when Marty appears, scaring Doc.
Marty explains that he came back to 1955 in regards to recovering the sports almanac from Biff to save the future. Marty then explains how the 1985 Doc was in the DeLorean and got struck by lightning, sending him back to 1885. Doc questions how Marty would know this, when Marty reveals the 70-year-old Western Union letter that was sent to Marty.
Doc reads over the letter, and finds out that the DeLorean is in an abandoned mine, with instructions for replacement parts for the 1955 Doc to help repair the time machine.
1955 Doc and Marty then go to the abandoned Delgado mine and recover the DeLorean, along with the repair instructions. As they prepare to tow the time machine back to Doc's laboratory, Doc's dog Copernicus stood in front of the tombstone for an Emmett L Brown, who died on September 7, 1885 (one week after the letter that was dated to Marty!). The tombstone also makes mention of being 'erected in eternal memory by his beloved Clara' (of which neither Marty or the 1955 Doc have a clue), and explains that Doc was 'shot in the back by Buford Tannen over a matter of 80 dollars.'
Marty and 1955 Doc take a picture of the tombstone, and then go to the local archives to try to find more information about Buford Tannen, but only find out that he was a short-tempered outlaw, with the nickname "Mad Dog." Marty and Doc also find information about the McFly family living in Hill Valley, as well as a picture of Doc in the archives. Even though Marty has been told to return to 1985, he tells 1955 Doc that he is instead going to 1885 and bring his friend back to the future as well.
After Doc manages to repair the time machine, he provides Marty with a cowboy outfit (albeit one that is almost too colorful for the old west), and takes them to a closed Drive-In theater near an open-area of land. Doc explains that since the open country hasn't changed much in over 70 years, Marty should be able to avoid anyone seeing the time-machine, or possible crashing the DeLorean.
Doc then sets the time circuits in the DeLorean to September 2nd (since the letter was written on September 1st. This is done so that Marty cannot interfere with Doc writing the letter and having it given to Western Union...to avoid a possible time paradox), and Marty drives off. However, once arriving in 1885, he finds himself almost run over by a group of Indians, followed closely by the United States Cavalry.
Marty drives the DeLorean across the rocky terrain, before finding a small cave to hide the DeLorean in. However, after getting out, Marty finds two things: 1) the rocky terrain has somehow ruptured the vehicle's fuel line, and 2) a bear is also in the cave.
Marty quickly rushes away from the bear, but falls down a nearby hillside, crashing into a fence, and falling unconscious.
When he wakes up, he finds himself in the home of Seamus McFly, and his wife Maggie, and their infant son, William. Marty soon realizes he is in the homestead of his ancestors, and claims that his name is Clint Eastwood, when they ask him who he is. During dinner, Marty explains his searching for the local blacksmith, and Seamus offers to help.
Giving him a hat and telling him to follow the railroad tracks the next day, Marty once again finds himself walking into Hill Valley...albeit a Western town that is still being developed. Even the iconic clocktower that Marty knows is still being constructed, with a dedication to take place the coming weekend.
Marty then goes to the local saloon, where he soon meets up with Buford "Mad Dog" Tannen. When he realizes just who Buford is and calls him "Mad Dog," the outlaw's anger riles, and he pulls out his gun, shooting at Marty's feet to make him "dance." In hopes to confuse Tannen, Marty begins to moonwalk like Michael Jackson, before accidentally knocking a spittoon full of tobacco juice on Buford. Now furious, Buford intends to kill Marty, who rushes out of the saloon, but not before Buford and his gang rope him, and drag him through town, before intending to hang Marty using a pulley and rope at the site of the clocktower building.
However, Marty is saved when Doc Brown appears, firing a specially-made rifle that breaks the rope, saving Marty. Buford then explains to Doc that the blacksmith owes him money from a recent shoeing that was made to Buford's horse. However, Doc explains that since Buford never paid him for the job, he doesn't have anything to answer for.
It is then that Buford explains why he feels Doc is responsible: his horse threw a shoe, which threw Tannen off his horse, also breaking a bottle of whiskey he was drinking. Tannen soon after shot the horse, and claims that Doc now owes him $5 for the whiskey, and $75 for the horse (the $80 talked of on the tombstone). When Doc refuses to pay, Tannen tells Doc that he'll soon end up dead, before he and his men ride off.
Going over to Marty, Doc is upset that his friend did not follow his instructions, but once they get back to the blacksmith shop, Doc is given the information about his eventual death. The mention of "beloved Clara" also doesn't ring any bells, until the town's Mayor stops by, and reminds Doc that he is scheduled to pick up the new school teacher coming in the next day. When the mayor mentions that her name is Clara Clayton, Marty and Doc now know who erected the tombstone in his memory.
Doc then decides that to avoid getting into any kind of time-altering love affair, he will simply not pick up Clara from the train depot the next, day and decides that they should get the DeLorean Marty came back in, and go. However, when Marty explains that the fuel line is ruptured, Doc's eyes go wide. Marty explains that as long as they have the Mr Fusion generator, they should be able to get back. It is then that Doc explains the flaw in Marty's thinking: Mr Fusion powers the time circuits and the flux capacitor, but the car still needs gasoline to run...gasoline that will not appear til' sometime in the 20th century.
Doc and Marty then recover the DeLorean, and try everything from a team of horses pulling the vehicle, to using an incredibly strong alcoholic drink. The horses cannot pull the DeLorean above 24mph, and the alcoholic drink ends up destroying the fuel-injection manifold on the car.
Realizing that the DeLorean can't run under it's own power, and they can't pull it, Doc figures they will need to push it up to 88 mph. Hearing the whistle of the train pulling into the station, he surmises a possible solution.
Doc and Marty go to talk to the engineer, and pretend to have a wager going to see if a steam engine could get up to 90 mph. The engineer explains that it most likely would depend on three factors:
1) If you had a straight stretch of track 2) If you weren't hauling any cars behind the train 3) If the fire in the engine could be made hot enough
Doc soon finds that the next train coming through the area will be on Monday morning at 8am. Checking a railway map, Doc finds what they are looking for: a long straight stretch that goes over Clayton ravine (oddly called Shonash ravine). In 1985, the tracks run near the Hilldale housing development, but Marty notes that in 1885, there is no bridge spanning the ravine.
Going out to see for themselves, Marty decides they have to change their plans (since the bridge over the ravine is scheduled to be completed in 1 1/2 years). Doc however, tells Marty he is 'not thinking fourth-dimensionally.' In 1985, the bridge will exist. With this reasoning, if they can reach 88mph before they reach the edge of the ravine, they'll time-travel to1985 when the bridge is completed, and simply coast right across.
As they prepare to head back to town, the panicked cries of a woman on a runaway buckboard wagon catches their ears. Doc manages to save the woman before the wagon uncouples from the runaway horses, and crashes over the side of the ravine.
The woman thanks Doc for saving her life, and reveals herself to be Clara Clayton. Doc and Marty escort her to her home adjacent to the town's schoolhouse. Doc explains to Clara that he'll clear up the issues with the owner of the buckboard rental business in town, and tells Clara that he also has a shop. However, he falters by first saying he's a scientist, which piques Clara's interest. Marty eventually tells Doc they have to be going, and they head off.
As they go a ways off, Doc makes mention how 'Ms Clayton almost ended up at the bottom of Clayton Ravine.' It is then that Marty remembers the history of the ravine that was taught to him in school: Clayton Ravine was named after a school teacher who fell in there 100 years ago (meaning 1885). Doc now realizes that they have changed history in some way, and curses inventing the time machine, feeling it has now continued to ruin things.
The next day, Doc has finished putting railroad wheels on the DeLorean, and shows Marty a scale miniature of his plan for getting them back:
The next night, they'll load the DeLorean onto the tracks along the stretch near an abandoned silver mine. When the 8am train leaves the station on Monday morning, theyll stop it at the switch track, uncouple the extra cars and then 'borrow' the locomotive, and use it to push the time machine. Doc calculates that they'll get the train up to 88mph, time travel back to 1985, and coast across the completed bridge.
Marty notices a windmill marked with a sign saying "Point of no return." Doc explains this is the fail-safe point. At this point, they can still stop the train before it falls into the ravine, but once they pass the windmill, there's no turning back.
The explanation is cut short when Clara appears. Clara has brought her telescope to Doc in hopes he might be able to fix it, as it was damaged in the accident. Doc quickly explains he can fix it and have it done that evening. However, Clara reminds him that the Town Festival will take place, but Doc still says he'll have it fixed by then. Clara then leaves, saying she hopes to see Doc (whom she calls "Emmett") and Mr. Eastwood there.
At the festival, the clock that will eventually grace the clock tower is activated, and a number of the citizens can have their photo taken in front of it. Marty and Doc decide to pose with the clock, as it has so far played a big role in their lives.
As the festival goes on, Doc meets Clara, and the two dance. Meanwhile, Marty takes part in a Colt firearms demonstration, and meets up with Seamus, Maggie, and William McFly again.
Meanwhile, Buford and his men have come to town, with Tannen intending to take care of Doc. After surrendering their firearms Marshal Strickland and his Deputy, the group enters, but not before Buford pulls out a concealed, small gun called a Derringer. Buford ends up sneaking up on Doc, threatening to shoot him. However, once he catches sight of Clara, he demands a dance. Doc becomes the gentleman in the moment and demands that he'd rather be shot, but Clara says she'll dance with Buford to save Doc. Clara dances with Buford for a bit before kicking him in his shin. This causes Buford to strike Clara, knocking her to the ground, before Doc's voice shatters the moment, yelling for Tannen to stop what he's doing.
"Damn you, Tannen!" shouts Doc.
"No," says Tannen, pointing the Derringer point-blank at Doc, "I damn you. I damn you, to hell!"
However, before Tannen can fire, Marty grabs a pie-plate, and flings it, knocking off Buford's aim. Marty demands that Tannen leave his friends alone, but Tannen then manages to provoke Marty by calling him "yellow."
Wanting to prove Buford wrong, Marty agrees to a dual at 8am on Monday. After Buford and his gang leaves, Doc has a few words with Marty, but not before Clara comes up, and Doc says he'll take her home.
Marty is then accosted by several men who are ecstatic that he stood up to Buford. One of them is the Colt firearms man, who gives Marty a Colt Peacemaker to use in the duel (with the promise that if Marty loses, the firearms man gets the gun back).
The only naysayers in the group are Marty's ancestors, who chastise him for giving in and not just walking away. The conversation turns to Seamus' brother, Martin. Martin was a man who was always provoked into fighting, until one fight ended up being the death of him.
Back at Clara's house, she and Doc are watching the stars, when their conversation turns to Jules Verne, an author whom both of them love, and Doc and Clara realize they have each met someone very special.
The next morning, Marty goes out walking and encounters Doc, having come back from Clara's, with a big smile on his face. As they walk through town, they one of the stores has finished making new tombstones...one of them just like the one seen at the Boot Hill Cemetery in 1955. Doc checks the photograph, and notices the tombstone and the date are still apparent, but there's no inscription on who is buried there.
As they continue to talk, the town undertaker comes by, measuring Marty for a coffin. When Marty asks why, the undertaker explains that there are betting odds in town that he will lose...and Doc explains that the tombstone could now be meant for Marty.
"Great scott," says Marty, realizing he could soon end up dead.
"I know, this is heavy," says Doc.
Doc then notices the Colt Peacemaker that Marty is carrying, and Marty explains that he intends to get back at Tannen for calling him 'yellow.' Doc chastises Marty for going through with this, and explains that his actions also cause an accident in his future. Marty is now curious about this unmentioned information about his future, but Doc refuses to say more.
Later that evening, setting up the DeLorean on the rail tracks, Doc explains that he is not going back, and intends to stay with Clara. However, after some talk, Marty tells Doc that this could very well continue to ruin the space-time continuum. Doc regards his friend's request, but still decides to go to Clara, to say goodbye.
Going to her house, Doc attempts to say goodbye in a subtle way, but Clara realizes he is keeping something from her, and wants to know the truth. Wanting to be honest with her, he explains that he is from the future and is going to return there the next day. Instead of understanding, Clara feels that he is lying as a way to say he doesn't love her anymore.
Heartbroken, Doc goes to town, and into the saloon, requesting whiskey. A salesman sees Doc, and engages him in conversation. As the conversation they are discussing mentions the word 'future,' Doc then begins to preach about what the future will bring.
The next morning, Marty wakes up, but finds Doc gone. Heading into town, he finds him still at the saloon, still awake after all this time, the untouched whiskey on the bar. Marty manages to shake his friend out of his depression, and the two head off...but not before Doc drinks a toast to the future...with the whiskey knocking him out cold!
The bartender mixes a concoction that manages to wake Doc out of his stupor, but still has him knocked out. As Marty and the bartender continue to try and revive Doc, Seamus arrives in the bar, claiming that 'something told him he should be there.'
Just as it seems things can't get any worse, Buford arrives, and demands the duel to take place immediately. The others in the bar demand Marty fight Buford, but seeing Seamus looking at him, and thinking of the consequences of his actions, Marty decides not to go through with it...just as Doc revives!
The two try to sneak out the back of the saloon, only to be seen by Buford's gang. Doc is captured, while Marty ends up diving into the building next door. Buford then gives Marty an ultimatum: either come out in 1 minute, or Doc will be shot.
Meanwhile, heartbroken from the 'lie' she was told, Clara has boarded the 8am train, intending to head to San Francisco. As she sits in one of the coaches, the salesman who was talking to Doc the previous night tells the guy sitting next to him about the 'heartbroken' man he met the previous night, who had a girl he loved named Clara. Hearing this, Clara asks and confirms that it was Emmet he was talking to. Pulling the brake cord on the train, the engine barrels to a stop, and she rushes back towards Hill Valley.
Back in town, Buford's minute is up, and Marty appears. Marty throws down his weapon, claiming he wishes to settle the dual 'like men.' However, Buford shoots Marty in the chest, and he goes down. Chuckling over his kill, Buford is then shocked when Marty rises up from the ground, revealing the steel door to a furnace under his clothing. Marty gets in several good punches, before Buford finally is knocked out, and collapses into a cart of manure.
During the battle, Buford was knocked into the tombstone that was in the photo. As Marty and Doc look at the photo, the tombstone disappears. With their business now about getting back to the future, Marty gives Seamus the Colt Peacemaker, and he and Doc head off towards the train.
Meanwhile, Clara has made it back to town, but finds Doc's blacksmith shop deserted. However, her attention is then drawn to the miniature, of which sits a strange vehicle with the words 'time machine' written on it.
Doc and Marty manage to 'borrow' the locomotive, and switch it over to the new track. Prepping the DeLorean and the train, Doc pulls out some colored logs that he calls 'presto logs,' which will help push the train to the desired speed they need.
After the first two logs go off, Doc attempts to climb onto the DeLorean, but not before hearing the steam whistle of the train! Turning back, Doc sees that Clara has caught up to the train, and is now aboard, calling out that she loves him! Doc intends to go back to the cab, but just then, the DeLorean passes the windmill, cancelling any chance to stop the train.
Doc then decides that they will then take Clara back with them, and has her climb out to him. However, just before they reach each other, the final log explodes in the furnace of the train, jolting the engine and causing Clara to almost fall over the side.
Marty helps Doc by throwing him the hoverboard, which Doc uses to save Clara. Marty watches as the two hover off to the side, before shutting the door. The DeLorean then reaches 88mph and disappears...with the locomotive barreling over the side of the ravine, and exploding in a huge fireball.
Marty then finds himself back in 1985, as the DeLorean coasts over the completed bridge (now spanning "Eastwood Ravine"). As the DeLorean coasts to a stop...a train whistle is heard, and Marty sees a diesel engine barreling head-on towards the DeLorean! With no time to save the car, Marty jumps clear as the engine plows into the time machine, destroying it into numerous pieces. Once the train has passed, Marty looks over the wreckage, and finds the Flux Capacitor and the Time Circuits (both of which give a small flash before falling silent).
"Well Doc," says Marty, sadly, "It's destroyed. Just like you wanted."
Returning to the Lyon Estates, Marty is ecstatic that everything is back to normal, including his family and Biff (no longer the tyrant of 1985-A from the second film, but the secretly-bitter auto detailer). Worried about Jennifer, Marty gets in his Toyota 4x4, and goes to her house. Waking her up, Jennifer tells Marty that she had a terrible nightmare.
As they drive past the still-in-development Hilldale housing complex, one of Marty's classmates named Needles pulls up next to the two, and challenges Marty to a race. Marty declines at first, until Needles calls him 'Chicken.' However, when the light they are at turns green, Marty throws his vehicle into reverse, not going through with the race.
As he and Jennifer watch, A white Rolls-Royce pulls out of a sidestreet, and Needles barely misses it. Marty remarks how he almost hit that car, causing Jennifer to reach into her coat pocket...finding the "You're Fired!" fax from the year 2015, with the words slowly fading away (proving that Marty's decision has now changed their future).
The two return to the wreckage of the DeLorean, only to be blown back as a vintage steam-engine appears...being driven by Doc Brown! Doc then introduces the two to Clara, as well as their sons: Jules and Verne. Doc then tells Marty that he decided to return to get Einstein (his dog), and to let Marty know he was all right.
Doc also presents Marty with a framed picture of the two of them, taking at the clock unveiling in 1885.
Jennifer then tells Doc of the fax she had from the future, that is now erased. Doc explains that this simply means their future is theirs to make of it what they will.
Doc then prepares to return with his family back in time.
"Hey Doc," asks Marty, "Where are you going now? Back to the future?"
"Nope," says Doc, with a smile and a wave," already been there!"
As Marty and Jennifer watch, The steam engine's wheels fold underneath, and it rises into the air, circling around, before reaching 88mph, and traveling back in time.
(note: my synopsis is overly-detailed because of the layers of the story. Back to the Future as a trilogy is very intricately layered, and try as I might, it seemed I could not condense it down due to how certain items tend to link into previous storylines or plot-points. Back to the Future is my favorite trilogy, and I just want the details to be accurate)
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