Summary

  • Back to the Future movies showcase the chaos of altering timelines through time travel, creating multiple timelines and a big mess.
  • The series is loved for its intersecting and altering timelines without being overly bogged down by scientific details.
  • Marty and Doc change history, creating 8 separate timelines throughout the trilogy.

Thanks to the meddling of Marty (Michael J. Fox) and Doc (Christopher Lloyd) in their Delorean, there are multiple timelines in the Back to the Future movies. Each chapter showcases the pitfalls of escaping to other points in history and the future, and between Marty and Doc Brown's altering of the past (and future), they make a pretty big mess. Of course, the Back to the Future films were never meant to be a blueprint for time travel. Arguably the most engaging thing about the series is that its timelines intersect and alter without being bogged down by every single real-life detail of quantum physics.

The result is three films — and a 10-minute short from 2015 in which Doc Brown saves the world from a nuclear apocalypse — that continue to captivate viewers. What begins as an accidental journey into the past rapidly evolves into something far more chaotic and fun. The events of the first Back to the Future movie are somewhat straightforward. It isn’t until Back to the Future Part II, which splits its action between the past and future, that things get hectic. By the time the third movie in the trilogy concludes, there are 8 separate timelines seen in Back to the Future, most of which were created by Doc or Marty changing history.

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1 The Prime Back To The Future Timeline – 1985

This Is Where Marty McFly's Story Starts

Principal Strickland Slacker in Back to the Future.

Audiences get their first introduction to Marty McFly in the then-present day of 1985. It’s immediately clear the concept of time is a major factor in the film, as Marty, busy playing guitar at the errant Doc Brown’s home, realizes the numerous surrounding clocks are 25 minutes slow. He’s late for school, and a mad rush ensues to get to class. Later that day after school, Marty is asked for a donation to save the local clock tower, which was struck by a bolt of lightning during a terrible storm in 1955 at precisely 10:04 pm and never fixed.

That night, he meets the Doc at the Twin Pines Mall and is introduced to the time machine — a converted Delorean powered by plutonium. But when Doc is murdered by a group of Libyan terrorists out for revenge after being given a fake bomb in exchange for plutonium, Marty flees in the Delorean and accidentally sends himself back to 1955. This can be considered the Prime Back to the Future timeline and was ended thanks to Marty's actions in the past.

2 The Alternate Past Marty McFly Influenced – 1955

Marty Goes Back In Time & Screws Up His Parent's Meeting

Marty’s arrival in the past comes as a shock, and as he struggles to make sense of what’s just occurred, he locates Doc Brown. Doc originally chose November 5, 1955, while showing off the time machine to Marty in 1985. Its significance lies in it being the date that Doc came up with the concept of the flux capacitor – the device that enables time travel. After managing to convince Doc Brown he is from the future, the two create a plan to send Marty back to 1985. However, plutonium is not available in 1955.

The power surge needed to send the Delorean back to 1985 will have to come from the bolt of lightning expected to hit the clock tower. Marty spends a week in 1955 as Doc prepares for the storm, and keeps busy by attempting to undo the damage he has caused by preventing the first meeting between his father and mother. Finally, Marty succeeds in getting his father to stand up to local bully Biff Tannen, as well as ensuring his parents dance together and fall in love. Marty is successfully sent back to the future, but a new Back to the Future timeline has been created.

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3 The New Present Timeline Marty Created – 1985

The New Timeline When Marty McFly Betters His Parents' Lives

Doc Brown and Marty McFly looking shocking in Back to the Future

When Marty returns to 1985, he is ecstatic to be home. He again sees Doc gunned down by the Libyans, but this time Doc wore a bulletproof vest thanks to a letter of warning that Marty left him in 1955. Other things have changed as well in this Back to the Future timeline, but fortunately, they are good changes, brought about by making his father stand up to Biff in 1955. His family has become successful, with his father now a published author. Both his parents appear healthy, happy, and in love.

This is unlike the disengaged relationship in the 1985 timeline in which Marty’s mother appeared to have a drinking problem. Marty is delighted to learn that he now owns the 4x4 truck he had previously longed for, and Biff has been reduced to meekly doing chores for the McFly family. Unfortunately, not long after Marty is reunited with his girlfriend Jennifer, Doc returns from the future to tell the couple that they must accompany him back to the future to save their children.

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4 The Future Of Marty McFly's New Timeline – 2015

Marty Goes To A Back To The Future Date In The Future To Save His Son

Marty and Doc in an alley in the future in Back to the Future Part II

The journey to the future comes in Back to the Future Part II and requires Marty to prevent his son, Marty Jr. from joining Biff’s grandson Griff in a robbery. The robbery would see Marty Jr. sent to prison, with Marty’s daughter Marlene also incarcerated after attempting to break her brother out. Jennifer begins asking too many questions during the journey to 2015 and is rendered unconscious by Doc, so Marty undertakes the mission alone.

He succeeds but decides to buy a sports almanac that has the scores of every sporting contest from 1950-2000. When Doc learns what Marty has done, he throws the almanac out, as he did not invent the time machine for profit. But lurking in the shadows is Grandpa Biff, who gathers the almanac and later steals the Delorean. Marty, Doc, and Jennifer return to 1985 unaware of Biff’s meddling, which will create a new Back to the Future timeline.

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5 The New Timeline Created By Future Biff Tannen – 1985

Biff Tannen Changes The Timeline To Become Successful

At first, everything seems normal when Marty returns to Hill Valley. But when Marty attempts to return home in Back to the Future Part II, he discovers an entirely different family living there, the brand-new Back to the Future timeline. Marty quickly learns that this version of Hill Valley 1985 is nothing like the one he’d left behind. In the new present, his father is dead, his mother has married the richest man in town (Biff), and Doc has been committed to a psychiatric institution.

When Marty goes to confront Biff over what has happened, Biff confesses he was given a sports almanac in 1955 by an old man. The scores inside have made him incredibly wealthy over the next 30 years. Biff Tannen also reveals that he intends to kill Marty, just as he killed Marty’s father. After a chase through Biff’s hotel, Marty makes his way to the roof, where Doc rescues him using the Delorean.

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6 The Alternate Past Marty McFly Influenced Again – 1955

Marty Tries To Stop Biff Tannen From Changing The Future

Back to the Future Lorraine and Marty

Marty returns to the past again in Back to the Future Part II — this time to save the future. He and Doc arrive with the plan to steal back the almanac from Biff and destroy it. Once the almanac is destroyed, Biff will no longer be able to get rich and create the dystopian 1985 that they’ve just come from. The date is November 5, 1955 once again, with Marty and Doc arriving just before the Enchantment Under the Sea dance. But as is always the case when tampering with Back to the Future timelines, nothing is ever simple.

Marty must battle Biff’s goons, as well as Biff himself, in the struggle to regain the almanac and prevent the original 1985 timeline from being altered. After much effort, Marty succeeds in reclaiming the almanac — but just as Doc attempts to pick him up in the Delorean, it’s struck by lightning and disappears. The moment this occurs, a Western Union delivery man arrives with a letter for Marty. The letter is from Doc, who is safe and living in 1885. When Marty discovers that, in 1885, Doc will be shot in the back by Buford “Mad Dog” Tannen, Marty decides to go back and rescue him.

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7 The Alternate Past Doc Brown Influenced – 1885

Marty Heads To 1885 To Save Doc

After Marty arrives in 1885 in Back to the Future Part III, the Delorean develops a fuel line leak that renders it useless. Eventually, Marty and Doc create a plan that involves using a steam engine to push the Delorean up to the 88 mph required for a return to 1985. Despite Marty saving Doc Brown from being killed, Doc decides to stay in 1885 with the love of his life, Clara. Marty returns to 1985 alone. In comparison to the wild jumps backward and forwards in Back to the Future Part II, the third movie in the trilogy takes place mostly in the Wild West setting.

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8 The Final Timeline Created By Marty McFly – 1985

Marty's Final Back To The Future Date

The movie poster for Back to the Future Part III (1989) showing Marty, Doc and Clara

Marty successfully arrives in 1985, but the Delorean is struck by a train and demolished. He returns home and goes for a ride in his new truck with Jennifer. While stopped at a red light, Marty is challenged to a race by local bully Needles, a character who worked with Marty in 2015 and who caused Marty to lose his job. Marty resists the pressure to race and Marty and Jennifer watch as a car narrowly avoids hitting Needles’ car. Had Marty raced, the car would have hit his truck.

As this realization sinks in, Jennifer finds a fax in her pocket from 2015 which had previously announced Marty’s firing. The text disappears before her eyes. The 2015 Back to the Future timeline when Marty isn’t able to pursue his dream of becoming a musician due to a persistent injury from a car accident, is erased, creating a better future for Marty and Jennifer. Moments later, Doc returns to 1985 in a new steam-powered time machine. He married Clara and is the father of two children.

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9 The Griff Tannen Nuclear Apocalypse Timeline - 2015

Based On A Short Film On The DVD Set

Doc Brown Saves The World! Back to the Future

On the 30th anniversary of the first movie, a new box set of the trilogy added a ninth Back to the Future timeline with the short film, Doc Brown Saves The World. The short sees Doc send a message to Marty confirming a Nuclear Holocaust is coming thanks to Griff Tannen accidentally uploading a virus. Doc saves the day and sends Griff back to prison, but subsequently realizes he still has the "Quantum Mind Jar" he intended to leave behind in 2075. To add to the suggestion of changing more Back to the Future dates, another Doc Brown appears from the future.

  • Back to the Future Poster-1
    Back to the Future
    Summary:
    Marty McFly, a 17-year-old high school student, is accidentally sent 30 years into the past in a time-traveling DeLorean invented by his close friend, the maverick scientist Doc Brown. In 1955, he meets his parents when they were his age, and must step in to make sure they wind up together before he gets back to 1985.
    Release Date:
    1985-07-03
    Cast:
    Claudia Wells, Christopher Lloyd, James Tolkan, Thomas F. Wilson, Michael J. Fox, Wendie Jo Sperber, Crispin Glover, Marc McClure, Lea Thompson
    Director:
    Robert Zemeckis
    Genres:
    Adventure, Comedy, Family, Sci-Fi
    Rating:
    PG
    Writers:
    Robert Zemeckis, Bob Gale
    Runtime:
    116 minutes
    Budget:
    $19 million
    Studio(s):
    Universal Pictures
    Distributor(s):
    Universal Pictures