Before teenage mother Lorraine's infatuation could get much out of hand, Marty finally sets off to Doc's to set things straight.
He knocks on the front door, which is answered by someone with a crazy look in his eyes and some bizarro contraption on his head. Of course, who else it could be other than the young Brown.
The man drags Marty inside, attempting to perform one of his famously failed experiments on a random stranger. To no surprise, it fails.
Marty doesn't have the easiest time convincing his old buddy that he's actually from the future.
Saying "Doc... I'm from the future" just isn't cutting it.
A driver's license that expires in 1987 with a plastered birthdate that could very well mean that the owner isn't born yet also doesn't cut it.
Of course, there was also the photo of the McFly siblings with Sister McFly's sweatshirt saying class of 1984, which still isn't convincing enough due to "tampering".
When questioned about who is 1985's President, Marty could only truthfully answer Ronald Reagan.
However, it only spurned sarcasm even further as anyone else in the 1950s would laugh at having a Hollywood actor being in politics... much more so when it comes to the presidency.
The disbelieving tirade went on as Doc sarcastically list out all other stars being important members of the government.
Clearly, Doc isn't buying any of it… until Marty describes to him the moment inspiration struck and how the eccentric man came up with the idea for the flux capacitor—something no one else could possibly know.
With everything sinking in, the boys drive out to where Marty hid the DeLorean.
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Back at Doc's swanky pad, they hook up the video camera to the TV (incredibly, the 1985 cords are still compatible with 1955 electronic equipment).
Doc watches his older self in amazement and delight but goes a bit ballistic when he gets to the part about the 1.21 "jigowatts" of electricity to the point that he says "Great Scott!"
As it turns out, Marty's got a few problems.
Problem Number One: 7-Elevens are not yet carrying weapons-grade plutonium, so getting back to 1985 may be an issue.
Since the procurement of plutonium is not really an option in 1955, they stumble upon the ingenious and oh-so-fortunate idea of using a bolt of lightning—the one that is due to screw up the clock tower in about a week—to generate the power needed to send Marty back to 1985.
So he's got a week to chill…but unfortunately, it's not going to be much of a relaxing vacation.
Because he bumped into his parents and threw the course of history all out of whack, Doc informs Marty that he's got to figure out a way to get mom and pop back together, or there won't be a Marty McFly to send back to the future.
Problem Number Two: there's this bully named Biff (his father's tormentor in 1955 and supervisor in 1985) who keeps getting all up in his business.
And Problem Number Three: he accidentally interfered with his mother and father's would-be romance, and now has to make sure they still get together, so he doesn't become erased… from existence.
For Cameron in the crowd with a time-travel film in his resume, this consequential take on the concept is clearly different from his pre-determined 'Reese-is-always-meant-to-travel-back' idea.
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In the week leading up to the event, Marty does his best to convince his father, George, to take his mother, Lorraine, to the Enchantment Under the Sea dance… but ends up taking her himself.
Early attempts to get his parents' acquainted fail, and Lorraine's infatuation with Marty only deepens.
Granted, having the name Calvin Klein and hip-skateboarding 1955 bullies and their car under a dirty ditch just puts anyone's cool points up an entire notch. Of course, it also didn't help that George McFly is super bumbly through and through.
Lorraine asks Marty to the school dance. He plots to feign inappropriate advances on Lorraine, allowing George to intervene and "rescue" her.
In the end, they could only go with this idea of having Marty tick Lorraine off, then have George step in and be the hero. Oh, the best-laid plans…
But the plan goes awry when Biff's gang locks Marty in the trunk of the performing band's car, while Biff forces himself onto Lorraine.
George arrives expecting to find Marty but is assaulted by Biff. After Biff hurts Lorraine, an enraged George knocks him unconscious and escorts the grateful Lorraine to the dance. Note: do not make George McFly angry. You wouldn't like him when he's angry.
So yeah, George clocks Biff, and then gets lucky that Lorraine is incredibly attracted to shows of violence. They're totally back on.
The band frees Marty from their car, but the lead guitarist injures his hand in the process.
Of course, everything was not saved yet as Marty's sibling photo is still being wiped and Marty himself is... phasing out.
Marty takes the injured guitarist's place and performs to set the mood so that George and Lorraine share their first kiss!
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With his future no longer in jeopardy, Marty heads to the courthouse to meet Doc.
Doc discovers a letter from Marty warning him about his future and destroys it, worried about the consequences.
Okay, time to return to 1985. After a few little snafus (well, it can't go perfectly, obviously), the lightning trick works and Marty is home at last.
To save Doc, Marty had re-calibrated the DeLorean to return ten minutes before he left the future. The DeLorean breaks down again though, forcing Marty to run back to the mall.
He arrives as Doc is being shot. While Marty grieves at his side, Doc sits up, revealing he pieced Marty's note back together and wore a bulletproof vest.
It turns out that he was able to warn Doc about the hail of gunfire from the Libyans, and Doc prepared himself by donning a bulletproof vest. Good thing none of those bullets hit him in the face.
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In the crescendo, Doc takes Marty to his 1985 home before he departs to 2015 in the DeLorean.
Things are different now though... but in a good way.
George is a together, successful guy instead of the sniveling brown-noser he was in the old 1985.
Lorraine is no longer an alcoholic.
Biff is now completely under George's thumb, and even Marty's house is way less depressing.
As it turns out, Marty just had to go through an entire early day's assistance to an eccentric doctor to change a lot of things from how they had been.
By the morning he wakes up, he discovered his father is now a confident and successful science fiction author, his mother is fit and happy, his siblings are successful, and Biff is a servile valet in George's employ.
Also, Jennifer is no longer the unwanted girlfriend but someone that Lorraine accepts and regularly hangs out at the McFly's.
Like how most films end, the sweethearts should share a sealing kiss...
Unfortunately, it was cut short as future-ized Doc shows up at the last minute and tells Marty and Jennifer there's something wrong with their kids in the future. It was Back to the Future... again!
The film ends with the trio boarding the DeLorean and Marty being skeptical. "Hey... Doc. We better back up. We don't have enough road to get up to 88."
To that, Doc only says with his cool shades on. "Roads? Where we're going we don't need... roads."
Most of the premiere audience was as skeptical as Marty as well... but the grand soundtrack sounded out...
And to the skeptic's surprise... the DeLorean lifted from the road it's at... its wheel's slanted to propel... and the boosters in its back zoomed it up to neighborhood skies...
The time travel blaze was set off and the Back to the Future title was plastered with 'I'.
The expectation for the sequel was set but that was just a build-up for the next...
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As of now, with credits rolling, the people in the premiere just stood up and applauded the film they just saw for what it was.
Be it execution, performance, concept, intrigue, humor, and all that. The film hit all its marks and the value in entertainment was guaranteed.
'Back to the Future' showed them a film that was just great in many ways.
Obviously, there are a lot of nuances and deep meanings to dig through but many folks in the premiere could only care for that later as they were caught up in the praise that their surrounding peers had for it.
Clapping and standing ovations were sort of a tradition for film premieres but this time... it may be pure respect through and through!