Is Back to the Future the greatest science fiction movie ever made? To quote Michael Scott, "We really can't say. But, yes."

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The movie was an immediate success and is still going strong to this day. It's hard to say what makes Back to the Future such an endlessly enjoyable classic, as the answers are truly numerous. The cast, the period setting, the humor and heart, the Oscar-caliber writing (literally, it was nominated) - all combined to create a truly timeless classic. And, as is often the case with movies like this, the making of Back to the Future proves just as interesting as the movie itself.

The Yearbook Genesis

Marty and George perform the same action in Back to the Future

Ideas come to people in numerous ways - including high school yearbooks. The movie's co-writer, Bob Gale, was visiting his parents at their home when he began leafing through his father's high school yearbook. It was then that he made an important realization - his father had been president of his graduating class.

This intrigued Gale, as he didn't personally know the president of his graduating class, leading him to believe that he and his own father wouldn't have been friends in school. The idea for a son attending school with his own father was born.

The Original Time Machine

Marty and Doc witness time travel

The DeLorean has entered the public consciousness thanks to its use in Back to the Future. Even to this day, it makes for one of the most unique time machines in movie history. And yet, the original idea wasn't a DeLorean - it was a fridge.

Yes, Gale and co-writer Rob Zemeckis originally envisioned the time machine as a fridge, but Zemeckis had concerns that children who watched the movie would attempt to travel back in time and accidentally lock themselves in the family fridge. The machine was changed to a DeLorean, as it worked for the UFO gag.

Why Does Doc Have A Giant Amplifier?

Marty stands in front of the amplifier

One of the movie's key unanswered questions lies in the personal relationship between Marty and Doc. Why is a teenager friends with this wacky, much older scientist? The answer seemingly lies in the massive guitar amplifier housed in Doc's garage.

But therein lies another question - why does Doc have a giant guitar amplifier in his garage? It doesn't really matter, because this was nothing but a quick story fix. The writers couldn't think of a good reason for Marty and Doc to know each other, so they conceived of the guitar amplifier to handwave it away.

They Had Incredible Difficulty Finding A Distributor

Marty and Lorraine sitting on a bed in Back to the Future

While Back to the Future is obviously a massive success, no one believed in it at the time. So much so that Zemeckis and Gale pitched the movie for four years without any success. They originally took the script to Columbia, but they didn't like how tame the story was.

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At the time, the most popular teen movies were controversial, overtly-sexual fare like Porky's. Listening to Columbia's criticism, they decided to take their script to the more family-friendly Disney. However, they also dismissed the idea owing to the Oedipal relationship between Marty and Lorraine.

Romancing The Stone

Jack T Colton (Michael Douglas) and Joan Wilder (Kathleen Turner) swing from a vine in Romancing the Stone

Romancing the Stone is a comedy adventure movie released in 1984, and it has everything to do with the creation of Back to the Future. Director Robert Zemeckis and Bob Gale had made two movies under Steven Spielberg called Used Cars and I Wanna Hold Your Hand. Both bombed. And while the duo thought of involving Spielberg in Back to the Future, they didn't want to produce another bomb with him.

Zemeckis went on to make Romancing the Stone, which proved a big hit. Now more confident (and more popular), Zemeckis approached Spielberg. The rest is history.

The Creative Work Of Sidney Sheinberg

A screenshot of Marty McFly and Doc Brown from Back to the Future

Sidney Sheinberg served as the CEO of Universal for 40 years and is famous for discovering Steven Spielberg in the late '60s. Mr. Sheinberg was enthusiastic of the script and offered some of his own creative suggestions. The goofiest was changing the title from Back to the Future to Space Man from Pluto, despite this not making a lick of sense.

No one agreed. However, some of his suggestions did make it into the movie, like replacing Doc's chimpanzee with a dog and re-naming Marty's mother after his wife, Lorraine Gary.

Eric Stoltz

eric stoltz BTTF

One of the more famous tidbits regarding production is that Eric Stoltz was originally cast in the role of Marty. However, this proved a terrible decision for all involved - including Stoltz, who claimed that he was not right for the role. Robert Zemeckis reportedly didn't like Stoltz's work for a variety of reasons.

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He believed Stoltz was too serious in the role, and he thought Fox had a more effortlessly "cool" personality that would fit the character better. Stoltz was released on good terms and Fox was hired, making movie history in the process.

The Many Choices Of Doc Brown

Christopher Lloyd as Doc Brown in Back to the Future

Marty wasn't the only character to face significant actor changes. Christopher Lloyd is magnificent in the role, but two actors were considered before him. John Lithgow was everyone's first choice and was seriously considered for the role, but prior commitments forced him to turn it down. Jeff Goldblum also auditioned for the role.

However, it obviously ended up going to Lloyd, who was convinced to take the role by both his wife and producer Neil Canton, who had worked with him on a movie called The Adventures of Buckaroo Banzai Across the 8th Dimension.

The Original Biff

Biff threatens Marty

Biff was yet another character who went through some changes - mostly regarding his physical stature. An actor named J.J. Cohen was the original choice to play Biff, but he was considered too short and unimposing opposite Eric Stoltz, who stands around six feet.

Thomas F. Wilson was brought in instead, who stands at a more commanding 6'2''. This contrast in height and build was greatly exaggerated when Stoltz was replaced by Fox, who measures in at a tiny 5'4''.

Fox Literally Worked Around The Clock

Doc and Marty watch the DeLorean

Michael J. Fox remained a very busy man indeed throughout production of Back to the Future. He was also working on Family Ties at the time, and his contract stipulated that it receive priority. Therefore, Fox would work on Family Ties throughout much of the day and then work on Back to the Future between 6:30 and 2:30 in the morning.

It was only then that he got some sleep, only to return to the set of Family Ties the next morning. This bizarre schedule also forced production to film all outdoor daytime scenes on the weekends.

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