Buzz
The beloved Back to the Future we celebrate today wasn’t the first version of the script. Surprisingly, there were at least four earlier drafts, each brimming with peculiar details that were ultimately left out of the final movie. Screenwriters Robert Zemeckis and Bob Gale have generously shared glimpses of the initial drafts, offering fans a chance to explore a version of the story without Johnny B. Goode, lightning strikes, or the iconic DeLorean.
Get ready for a wild ride as we accelerate to 88 miles per hour.
10. Marty McFly Was Originally a Lawbreaker
The iconic beginning of Back to the Future is flawless. It begins with a gradual sweep across a room adorned with clocks, a fitting visual for a film centered on time travel. Next, we’re introduced to the protagonist, Marty McFly, as he connects an electric guitar to a massive amplifier.
The initial draft lacked this elegance entirely. Instead, the screenplay’s first version kicked off with a completely unrelated scene.
EXT. OUTER SPACE The MOTHER SHIP ascends above Devil’s Tower and glides into space, accompanied by John Williams’ score. It quickly becomes clear that we’re witnessing the closing credits of “Close Encounters.”
That’s correct. Back to the Future initially started with the conclusion of an entirely different movie. Soon after, the reason behind this choice is revealed.
PULL BACK TO REVEAL that the image is displayed on a TV monitor . . . as we continue PULLING BACK, we uncover a collection of video equipment, where “Close Encounters” is being illegally copied from 3/4″ cassette to VHS and Beta.
The individual managing this operation is none other than Marty McFly. Surprisingly, the protagonist of our story is a movie pirate. It’s soon disclosed that the video equipment belongs to Doc Brown, who is also involved in this illicit activity.
Unsurprisingly, the studio disapproved of their lead character engaging in movie piracy, and this character trait was entirely removed from subsequent script drafts.
9. Doc Brown Was Initially ‘Professor Brown’
How would Back to the Future feel without the dynamic bond between its two central figures, Marty McFly and Dr. Emmett Brown? And how would their connection resonate if Marty didn’t affectionately call him “Doc”?
Interestingly, the original script draft tells a different story. In this version, Emmett Brown isn’t referred to as “Doc” but rather as “Professor.” Throughout the first draft, Marty addresses him as “Professor,” “Prof,” or even “Pro.” None of these titles carry the same charm as the iconic “Doc!”
But what field did Emmett Brown specialize in? Naturally, it was nuclear physics!
MARTY A few years back, he showed up at my place and offered me a job cleaning out his garage. He pays me 50 bucks a week, throws in free beer . . . and lets me dive into his incredible vintage record collection. (a beat) It’s wild to think he was once one of the world’s top nuclear physicists.
In the final cut of the film, Doc is portrayed as an eccentric inventor whom the townsfolk merely tolerate. His past is never explicitly explored. However, in this earlier version, it’s clear he was once a nuclear physicist. This intriguing detail about his background was eventually omitted by the time the movie was released.
8. The Flux Capacitor Originally Ran on Coca-Cola
In the theatrical version of Back to the Future, the DeLorean is powered by “regular, unleaded gasoline” and a significant amount of plutonium. However, the initial draft included an additional, unconventional energy source.
Early in the script, Marty decides to drop by Doc’s lab. Upon arrival, he finds Doc asleep. Acting like a typical teenager, Marty heads to the fridge, grabs a Coke, and begins exploring. He notices Doc’s latest invention, something he’s never seen before, and impulsively decides to pour Coke into it (because, well, why not?).
This action triggers the machine to spark and emit strange noises, startling Doc Brown awake. Intrigued, Doc adds more Coke to the experiment—which, incidentally, is the time machine—and it suddenly lights up, prompting Doc to rejoice over solving his energy crisis.
PROF. BROWN What’s in this stuff?
MARTY Nobody knows the formula for Coca-Cola. It’s the most closely guarded secret in the world!
This proves to be an incredibly practical fuel source, especially since Coke remains widely popular and accessible when Marty travels back to the 1950s.
7. A Nuclear Explosion Propels Marty Back To The Future
In the original Back to the Future, aside from ensuring his parents fell in love, Marty’s mission was to harness a lightning strike to hit his car precisely as he reached 88 miles per hour, sending him back to the future. While this is undeniably thrilling, do you know what’s even more exhilarating?
Nuclear explosions.
In the film, the flux capacitor requires a burst of 1.21 gigawatts to initiate time travel. However, in the initial draft, it didn’t rely on electricity but rather on rads—a unit measuring absorbed radiation.
The first script draft stated that the time machine needed 4,400 rads, an enormous amount. To put it in perspective, a dose of 1,000 rads is almost always deadly.
Acquiring such a massive amount of rads is far more challenging than generating electricity. For instance, a lightning strike wouldn’t suffice. In the 1950s, the only source capable of producing 4,400 rads was a nuclear explosion.
Fortunately, during the ’50s, the military conducted nuclear tests in the Nevada desert. Therefore, Doc—or in this version, the Professor—concludes that the only way to send Marty back to the future is to drive him and the time machine into a testing zone and expose them to a nuclear blast.
This is precisely what happens. But with 4,400 rads being four times a lethal dose, how does Marty avoid severe radiation poisoning?
6. The Time Machine Was Originally a Refrigerator
The first draft of Back to the Future was penned in 1981, well before the DeLorean became iconic. It’s hard to picture the film without its legendary car. What alternative could they have used? A different vehicle? An aircraft? A space-age capsule?
In the ’80s, Doc constructs a heavily shielded container capable of withstanding extreme radiation. While it lacked flair, it served its purpose. In the ’50s, pressed for time, Doc scrambles to find something with basic radiation shielding and enough space to accommodate a person.
He discovers a refrigerator.
Recall Indiana Jones and the Crystal Skull? Back to the Future beat them to it. The team concluded that the lead lining in certain refrigerators would provide sufficient radiation protection to keep Marty unharmed.
That’s correct: Marty was strapped into a lead-lined fridge and sent into the Nevada desert to be struck by a nuclear explosion. Fortunately, this idea was scrapped when concerns arose that children might attempt to time travel by climbing into refrigerators.
5. Doc Brown Was Originally a Plutonium Thief
The challenge of sourcing enough energy for time travel has always been central to Back to the Future. While earlier attempts involved nuclear bombs and lightning, the 1980s version relied on plutonium.
In the final script, Doc Brown acquires the plutonium needed for time travel from Libyan terrorists. He deceives them by promising to build a bomb but instead uses the plutonium for his own purposes.
In the original draft, Doc bypasses intermediaries entirely. He infiltrates a power plant and steals the plutonium directly. This leads to significant consequences when federal agents confront Marty, believing Doc intends to create a bomb. Instead of being pursued by Libyans, Doc is shot by federal agents who mistake him for a terrorist.
REESE (to Prof. Brown) You!! Shut it down!! Now!!
PROF. BROWN No! Get out!! I’m in the middle of an experiment!!
4. Doc Brown Originally Had a Pet Monkey
Quick question: Who was the first character to travel through time in Back to the Future?
If you guessed Einstein, Doc Brown’s dog, you’re right. In the movie, Doc tests his time machine by sending Einstein one minute into the future using a remote control and a stopwatch. When the dog returns unharmed, Doc celebrates the success of his groundbreaking invention.
The initial draft didn’t feature Einstein. Instead, it included a monkey named Shemp, dressed in a red coat and hat, resembling an organ grinder’s monkey. Unlike Doc’s dogs, Einstein and Copernicus, Shemp isn’t named after a renowned scientist. It’s likely Shemp was inspired by Shemp Howard, one of the original Three Stooges.
Interestingly, the term “Fake Shemp” refers to replacing an actor with another using prosthetics and camera tricks. Back to the Future: Part II faced a lawsuit involving this concept when Crispin Glover, who played George McFly in the first film, sued the producers for using his likeness without consent. This led to the Screen Actors Guild prohibiting the use of Fake Shemps.
In the original script, Shemp becomes the first time traveler when Doc sends him two minutes into the future. However, unlike Einstein, Shemp doesn’t have a 1950s counterpart and disappears after his pivotal scene.
3. The Ending Was Completely Different Originally
In the final scene of Back to the Future, Marty returns home to discover that his actions in the past had significant effects. His parents are happily together, his sister is well-liked, his brother has a successful career, and Biff is no longer a laughingstock. It feels like a perfect conclusion.
However, this wasn’t always the case. In the original script, Marty comes home to a completely altered reality. His father is now a professional boxer.
Additionally, technology has drastically changed. Flying cars from the ’50s exist, plastic Coke bottles feature vintage pop tops, and robot butlers are commonplace—many of which were invented by Doc Brown. Rock and roll never emerged, the mambo remains popular, and the U.S. has expanded to 87 states. Unlike the final version, Marty’s time travel completely reshaped the world. This highlights the transformative power of a rewrite.
2. Doc Brown’s Vision Came After a Beer Bottle Incident
The Flux Capacitor is the key to time travel. In the final script, Doc Brown explains this to Marty, sharing the story of its invention. Essentially, he struck his head while hanging a clock and experienced a sudden vision.
This detail was still being refined as late as the fourth draft. In that version, Doc mentions hitting his head but evades Marty’s question about how it happened. Marty eventually learns the truth when he travels back in time.
When Marty travels back to 1955, Doc isn’t in the mood for conversation. In fact, he’s hosting a party and promptly dismisses Marty. Undeterred, Marty observes the party from outside the window, where he witnesses the following event.
Brown approaches the most attractive WOMAN at the party. He whispers something in her ear, and she responds by smashing a BEER BOTTLE over his head! Brown collapses, stunned. She storms off angrily.
Now we know the truth: Doc Brown’s failed attempt at flirting led to his head injury. Don’t feel too bad, Doc—your rejection ultimately led to the invention of time travel, so it wasn’t all for nothing.
1. Marty McFly’s Shoes Were Originally Green
While this might not be a major plot alteration, it’s certainly an odd one. Marty McFly’s outfit is iconic: a checkered shirt, blue jeans, Nike sneakers, Calvin Klein underwear, and, of course, the unforgettable orange vest. Show anyone these clothes, and they’ll instantly recognize them as Marty’s.
However, earlier script drafts reveal this wasn’t always the case. In the fourth draft, there’s no mention of the orange vest. Instead, Marty sports bright green shoes, baffling everyone around him.
SKINHEAD Biff—check out his shoes. This loser thinks he’s a leprechaun—he painted ‘em green!
This isn’t the only costume change. For instance, the movie’s novelization—based on a later draft—references a T-shirt featuring a patent schematic. This T-shirt appears in some early photos of Eric Stoltz as Marty McFly. It’s possible that when Michael J. Fox took over the role, the wardrobe was updated as well.
