Back to the Future – celebrating its 35th birthday this year – is rightly regarded as one of the best time-travel movies ever made.
It has been spun off into theme park rides and a cartoon series, turned its lead (Michael J Fox) into a movie star, boasted a mega-hit theme song (Huey Lewis and the News' 'The Power of Love') and is even the inspiration for a stage musical.
But as the movie's writer/producer Bob Gale remembers, it could all have turned out very differently.
A race against time
As fans of the trilogy already know, Michael J Fox wasn't the original actor cast to play teenager Marty McFly, who travels from 1985 back to 1955 in a DeLorean time machine, disrupting the first meeting between his (future) parents.
Eric Stoltz, best known for roles in Mask and subsequently Pulp Fiction, was hired as Marty and filmed Back to the Future for five weeks in late 1984 before he was replaced.
"Eric is a terrific dramatic actor, but as a naturally funny guy – not so much," Gale says. "Lea Thompson [who plays Marty's mother Lorraine] told us sometime later that she had a conversation with Eric on set and he felt that the movie was really supposed to be a tragedy.
"He told her to think about it from the point of view of Marty McFly – here he is in this 1985 world at the beginning of the movie, and at the end of the movie, he returns to this world that is kind of like what he left but actually is different.
"His parents are different people, and maybe his girlfriend is a little different, and his life is different. Eric thought Marty would be really miserable."
"That never occurred to us when we were making the movie," Gale continues, laughing, "but I think that kind of attitude permeated some of Eric's performance. Five weeks into filming, [director] Bob Zemeckis had about 40 minutes of cut-together footage and he said, 'I want you guys to look at this,' meaning myself, and producers Neil Canton, Kathleen Kennedy and Steven Spielberg, and he said, 'I don't think we are okay.'
"And we all watched the footage and we could see we had a problem. We had a black hole in the centre of this picture – I think those were the words that Spielberg actually used."
While actors are sometimes replaced before filming begins, it's rare for an actor to be replaced during filming – with the most notable examples being Colin Firth, the voice of Paddington until his dialogue was re-recorded by Ben Whishaw; Stuart Townsend, who filmed four days on The Lord of the Rings before being replaced as Aragorn by Viggo Mortensen; and Harvey Keitel, whose scenes in Eyes Wide Shut were redone with Sydney Pollack when Keitel couldn't return for reshoots.
But none of these actors were a movie's leading man whose character appeared in almost every scene, as Marty does in Back to the Future. So recasting the role was a major problem.
Michael J Fox had been the producers' original choice for Marty, but he was tied up working on the US TV sitcom Family Ties. Once it was decided things were not working out with Eric Stoltz, they decided to try for Fox once more.
"We went to the producer of Family Ties and I think we literally got down on our knees and told him the situation we were in," continues Gale. "He said that if we could shoot the movie around the schedule of Family Ties and if Michael was up for doing that, it was okay with him."
Despite Michael J Fox having to film nights and weekends on the movie, sleeping in the car that shuttled him between the set and the Family Ties studio, it was soon apparent that the producers had made the right decision.
"We were filming in a high-school parking lot," Gale remembers. "We had already filmed the same scenes with Eric Stoltz at Christmas. Usually when you are out at a location, local people come to watch you shooting, but nobody had showed up. So now we are back there in March 1985 and word gets around that Michael J Fox is in the picture.
"We had kids lined up seven deep trying to catch a glimpse of him. Bob Zemeckis and I looked at each other and we said, 'Wow, this kid is a really big star, maybe people will come and see this picture!' That was the first inkling we had that we might have lightning in a bottle."
The lightning strikes
In fact, the then-head of Universal Studios, Sidney Sheinberg, was so impressed with an early version of the movie that he moved the release date from late August of 1985 to the coveted July 4 Independence Day weekend in the US.
"The post-production guys worked 24 hours a day so that the movie was in theatres nine and a half weeks after the end of principal photography," Gale adds.
"It was totally unheard of to do that and we ruined post-production schedules in Hollywood for years as other studios looked at us and said, 'Well, if these guys can get a movie in theatres within 10 weeks, any movie can do that!'"
The success of Back to the Future in 1985 led to the studio asking for a sequel, and Bob Gale and Robert Zemeckis went on to film two more BTTF movies back-to-back in 1989.
Part II is remembered as being the darkest of the trilogy with Marty accidentally changing the future for the worst due to his actions in the past, and the movie ends on a cliffhanger that wasn't resolved until Part III came out six months later.
"People ask me if there is anything about the movies I would change," Gale says when asked about the bleaker Part II.
"I got into a heated argument with Tom Pollock, who was running Universal Studios at the time. When they were marketing the movie, I wanted to be totally upfront, letting people know there was going to be a third one before they even bought a ticket to the second.
"I thought that was really important, because I remember when I went to see The Empire Strikes Back, I walked out of the theatre and I was really upset – Han Solo is in carbon freeze, what kind of ending is that? And I remembered the Richard Lester Three Musketeer movies, where at the end of the first movie there was a trailer for the second one as he had shot both movies at the same time.
"That was what inspired us to put a trailer for Part III at the end of Part II – the studio was adamant we could not tell the public there was going to be a third part before that, that they could only find that out when they saw the second movie."
The third movie, released in 1990, is the final movie, and Gale, Zemeckis and the cast have no plans for a fourth. "The studio would have loved a fourth one, but at the end of Part III we literally put the words 'The End' at the end of the movie," Gale continues. "We wanted to make it really clear, it is done and we meant it."
It's unlikely Back to the Future will get a Ghostbusters-style 21st century reboot either. "No-one can do anything about Back to the Future without coming to us [Gale and his fellow producers] first," Gale explains. "Universal would be happy to have another Back to the Future but they know they are not going to get it, and they are living with that!"
While Gale has many souvenirs from the set to remind him of the cinematic joy that is Back to the Future – "I have a couple of hoverboards from Part II, a couple of versions of the Sports Almanac and a craftsman's table from Doc Brown's lab my wife wanted, but they wouldn't let me have the DeLorean car!" – there are new projects that he is involved with that will delight fans.
He joined Robert Zemeckis, Michael J Fox and fellow trilogy cast members Christopher Lloyd, Lea Thompson, Elisabeth Shue, Mary Steenburgen, and singer Huey Lewis to celebrate Back to the Future for Josh Gad's lockdown YouTube series Reunited Apart in May.
Viewers were also treated to a preview of the new Back to the Future stage musical that Gale has co-written, which opens in London in May 2021.
"One of our objectives in translating the movie to the stage was that if you had never seen the movie, you will still enjoy it," Gale explains. "And if you have seen the movie, you'll enjoy the musical even more because you will see familiar scenes, retold in different ways, plus little references and inside jokes.
"It celebrates the movie, and the fun thing for me adapting it is now we are looking back at 1985 the way in 1985 we were looking back at 1955. There are jokes in the musical that we never thought of at the time of the movie."
"Not least of which is the clothes," he adds. "We looked at the ensemble cast dressed in their '80s wardrobe and we wondered, did we have any clue how absurd we really looked back then?"
Back to the Future the Musical will be at the Adelphi Theatre, London, from May 2021. Tickets are available at www.backtothefuturemusical.com.
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