(CNN) -- On October 26, 1985, Marty McFly took a fateful journey in a Delorean, which sent him hurtling back to 1955.

Thus began one of the most successful film franchises in history, and 25 years after that date --- this Tuesday to be exact --- the "Back to the Future" trilogy is coming to Blu-Ray for the first time, including never-before-seen footage of the original Marty, Eric Stoltz.

CNN's Geek Out spoke to the film's producer and co-writer, Bob Gale, who shared memories of the struggle to get this modern classic to the screen.

CNN: How difficult was it to get this script produced?

Gale: The script was rejected over 40 times by every major studio and by some more than once. We'd go back when they changed management. It was always one of two things. It was "Well, this is time travel, and those movies don't make any money." We got that a lot. We also got, "There's a lot of sweetness to this. It's too nice, we want something raunchier like 'Porky's.' Why don't you take it to Disney?"

Well, we heard that so many times that Bob [Zemeckis, co-writer and director] and I thought one day, "what the hell, let's take it to Disney." This was before Michael Eisner went in and reinvented it. This was the last vestiges of the old Disney family regime. We went in to meet with an executive and he says, "Are you guys nuts? Are you insane? We can't make a movie like this. You've got the kid and the mother in his car! It's incest -- this is Disney. It's too dirty for us!"

CNN: Did you continue to make changes to the script as time went on?

Gale: We wrote two official drafts, and it was the second that we took around to everybody. One person who was very interested in that draft was Steven Spielberg.

We had made a few movies with him, and they were all considered flops. We told Steven that if we make the movie with you and it's a flop, we'll probably never work in this town again, because we'll be the guys whose movies get made because of their friend, Steven Spielberg.

Finally, Zemeckis goes off and makes "Romancing the Stone." It's a big hit, and suddenly everybody and his uncle wants to make Bob's next movie. The movie Bob [Zemeckis] wants to make is "Back to the Future." Being the loyal guy he is, he says, let's go back and give it to the guy who wanted to make it in the first place, Steven. We were the first non-Spielberg-directed movie to be made at his new company at Universal, Amblin Entertainment.

The head of Universal at the time, Sid Sheinberg, liked the script, but he asked for a couple of things to be changed. First, he was known as "Professor Brown," not "Doc Brown." He said that kids wouldn't like someone named "Professor," so let's change it to "Doc Brown."

His wife's name was Lorraine, the actress Lorraine Gary who's in "Jaws." The female character's name was changed to Lorraine, in honor of Sid's wife. He wanted that.

Also at first, Doc Brown didn't have a pet dog. He had a chimpanzee. Sid said no chimpanzees. "I looked it up," he said, "no movie with a chimpanzee ever made any money."

We said, what about those Clint Eastwood movies, "Every Which Way But Loose" and "Any Which Way You Can"? He said, "No, that was an orangutan." So, we have a dog.

Happy Marty McFly Day!

CNN: What was the most difficult part of production?

Gale: Casting was the hardest part. We didn't get that right the first time, as you know.

Once Michael J. Fox was in it, the hardest thing was the schedule. We had to shoot around Michael's "Family Ties" schedule. Michael would work on "Family Ties" at 9 in the morning. He'd work there til 5 or 6. He'd go over to Universal, and we'd work with him til 1, 2 in the morning. So shooting a movie under those conditions, that was hard.

CNN: "Back to the Future," at its core, is about kids' relationships with their parents. At what point did you get into researching time travel?

Gale: Well, we looked at a book on the aspect of putting a nuclear reactor in a car -- what would that be like?

In fact, the original ending to the movie was not the clock tower. It took place at a nuclear test site, where they literally had to harness the power of a nuclear blast to get back to the future. We researched that. That was scrapped when it turned out it would be very expensive to do that.

There was a version of that scene in the last "Indiana Jones." What they did was build these fake little towns and blow them up, which we researched.

We couldn't afford to go on location and do all that, so we came up with the lightning thing, which we had to research --- how much electricity was in a lightning bolt, and the electrical engineer that we spoke to pronounced it "jigowatt" instead of "gigawatt." Both pronunciations were correct, but neither of us ever heard the term before, so in the script, it's misspelled "jigowatt."

CNN: I've heard there were changes to what the time machine was going to be.

Gale: Way back in that second draft, it was going to be a "time chamber," not unlike a refrigerator, and Doc Brown had to carry it on the back of his truck.

When we started figuring out how to make the movie, Bob Zemeckis had a flash of inspiration and said, "It should be mobile. It should be built into a car. It could be a Delorean."

CNN: How deep did the time travel research go?

Gale: Paradoxes didn't require much research because both of us had seen old episodes of "The Twilight Zone" and old sci-fi movies. I also read a lot of Robert Silverberg and Robert Heinlein when I was in college, so all that paradox stuff goes without saying.

CNN: Any other past science fiction to which you were trying to pay homage?

Gale: In the first scene where Marty's turning up the amplifiers, there's a "CRM-114" on the equipment. That's an homage to "Dr. Strangelove." That's what the equipment is called in that movie, a favorite of Bob and mine.

CNN: Any truth to the rumors about another "Back to the Future" project?

Gale: No, those rumors keep going around.

Michael J. Fox really can't do it, and who wants to see another "Back to the Future" without Michael J. Fox? I sure don't.

As for rebooting it, the movies are great the way they are. We've seen franchises that go back to the well many years later -- and I'm not gonna name any of them, but you know what they are -- they're always disappointing. What it is in people's minds, that's such a high bar to reach. I don't know how you reach that bar. We'll just leave well enough alone.

CNN: Anything about the movie's contribution to pop culture that sticks with you?

Gale: One thing that people tend to forget is that skateboarding underwent a renaissance with "Back to the Future." Skateboarding was not really that popular in the 1980s until "Back to the Future" put it back in people's consciousness.

But certainly, the title is so great, people keep using it as headlines in articles, "This goes back to the future."

And in the DVD, there's a clip of Ronald Reagan in the 1986 State of the Union address, quoting the last line of the movie. That was so great, the president quoting the movie.

CNN: What do you think about the movie's legacy 25 years later?

Gale: 25 years ago, if somebody had told me, "Hey Bob, you know what you're going to be doing in 2010? You're going to be doing interviews for 'Back to the Future," I would say, "Get out of town!" It's amazing.