He told you he’d be back. Before you go and see the newest installment of the Terminator franchise, here are some things you may not have known about the first four movies in the series.

1. THE TERMINATOR CAME FROM A NIGHTMARE.

Director and co-writer James Cameron first thought of the idea for The Terminator while stressed out and fever-stricken in Rome during production on his low-budget horror movie, Piranha II: The Spawning, which he had reluctantly agreed to direct. After a hard night of editing his own cut of a movie he hated, Cameron dreamed of a solid chrome torso crawling out of an explosion and dragging itself across the floor. The director quickly cooked up the story of a robot assassin sent back in time to kill the woman whose son will become the savior of humankind, and The Terminator was born. Cameron has since disowned Piranha II and considers The Terminator his first film.

2. JAMES CAMERON DIVVIED UP THE WRITING DUTIES.

To turn his nightmare into a screenplay, Cameron recruited his friend William Wisher, Jr., who is only given an “Additional Dialogue” credit in the final film. Wisher would actually write the early scenes establishing Sarah Connor and the police interrogation sequences, while Cameron fleshed out most of the action scenes and the details involving the war between humans and the machines. Producer Gale Anne Hurd, who would eventually marry and divorce Cameron, also received a writing credit on the movie, though according to Cameron she didn’t do any writing at all. Hurd apparently only suggested script edits. (Cameron also sold The Terminator rights to Hurd ... for $1.)

3. THE MOVIE HAD A UNIQUE PITCH MEETING.

The script found its way to the desk of John Day, the head of low-budget movie studio Hemdale Pictures, who called Cameron in for a pitch meeting after Orion Pictures had already agreed to distribute the film nationwide. To woo the studio, Cameron had actor Lance Henriksen (who had appeared in Piranha II: The Spawning, and would go on to appear in The Terminator and Aliens) show up to the meeting decked out in costume as the titular cyborg who at that point had yet to be cast. Henriksen broke down the studio’s office door while wearing a ripped shirt, leather jacket, combat boots, and gold foil from a cigarette pack folded around his teeth. Daly loved the gimmick and Cameron’s pitch, which included detailed storyboards to round out his ideas, and greenlit the movie with a budget of $6 million.

4. THE STUDIO WANTED O.J. SIMPSON TO PLAY THE TERMINATOR.

Arnold Schwarzenegger first came to the attention of Cameron after the head of Orion Pictures had met the former Mr. Universe at a party. At that point, Arnold’s only legitimate acting experience had been in 1982's Conan the Barbarian, and he was eager to break into different roles. Orion originally wanted Arnold to play Kyle Reese, the human fighter sent back in time, and wanted former NFL star O.J. Simpson to play the Terminator.

Cameron initially didn’t like either choice, and took a meeting with Schwarzenegger with the intention of picking a fight with him and storming back to the studio demanding a new actor. Instead, the two clicked over Schwarzenegger’s vision for the titular villain, which instead caused Cameron to run back to the studio and suggest he play the Terminator; the actor was signed the next day.

Fun Fact: Sting was considered for the role of Kyle Reese before Cameron chose actor Michael Biehn. Biehn would go on to appear in Cameron’s next films, Aliens and The Abyss.

5. SHOOTING ON THE MOVIE ENTERED A STATE OF ARRESTED DEVELOPMENT.

After more than a year of preparation, Cameron was finally ready to start filming in the spring of 1983 when the producer of Conan the Barbarian, Dino De Laurentiis, exercised an option in Schwarzenegger’s contract to force him to appear in the Conan sequel, Conan the Destroyer, despite his Terminator contract with Cameron. The entire filming schedule for The Terminator had to be scrapped and delayed for nine months while Schwarzenegger went off to film the other movie in Mexico.

6. CAMERON USED THE DELAY WISELY.

During the forced delay on the start date for his movie, Cameron used the script for The Terminator as a writing sample to attract new writing opportunities around Hollywood. He eventually got a meeting at Brandywine Productions for a remake of Spartacus that took place in space, but when that fell through the production company floated another property to Cameron: the sequel to Alien. Cameron went back a week later with a script treatment for “Alien 2” that incorporated ideas from another script he had written called “Mother” where a gigantic alien creature fights the female lead while she is strapped into a huge mechanical exoskeleton. The studio loved his take, and hired him to write the Alien sequel.

On the very same day, Cameron was also hired by a different studio to write the second Rambo movie. Not wanting to let two opportunities slip through his fingers, Cameron took both jobs, and wrote the screenplays simultaneously. To complete both projects in a three-month period, Cameron estimated each would be two hours long with scripts at 120 pages apiece. He then divided the total working hours he would have during the three months by the 360 pages for both scripts and wrote that many pages per hour until they were both complete.

7. THE FINAL TERMINATOR DESIGN WAS IDENTICAL TO CAMERON’S NIGHTMARE.

Cameron originally wanted special effects legend Dick Smith to create the design for the Terminator’s skeleton. Smith was the genius behind the make-up for the iconic effects in The Exorcist and aging Marlon Brando in The Godfather, but Smith declined the offer, which left the opportunity open for his lesser-known friend, Stan Winston, to step in. Winston would go on to pioneer effects in such movies as Cameron’s own Aliens and Steven Spielberg’s Jurassic Park. Despite the fact that both Cameron and Winston would spend weeks sending each other preliminary design sketches about what the Terminator would look like, the final design was from the same sketch Cameron made after having his nightmare epiphany in Rome.

8. WINSTON’S TEAM WORKED HARD TO CREATE THE TERMINATOR SKELETON.

Seven separate artists worked around the clock for six months to create Cameron’s vision of the Terminator skeleton puppet. It was created using a clay, plaster, and urethane molding, which was then cast in a mixture of epoxy and fiberglass with reinforced steel throughout the rig. The whole skeleton was chrome-plated and distressed to look more realistic, and the final skeleton weighed more than 100 pounds.

When they tried to puppeteer the skeleton walking on set, Cameron thought the lumbering rig didn’t look real enough. To make up for the fake-looking walking, Cameron added a story beat that had the Terminator develop a limp after walking out of the fiery truck.

9. THE MUSIC HAS A UNIQUE TIME SIGNATURE.

The movie’s distinctive music was written and performed by composer Brad Fiedel. To create the iconic clangs of the film’s percussive theme, Fiedel recorded samples of himself banging frying pans together and then layered in synth melodies underneath using Prophet 10 and Oberheim analog synthesizers. While blending the two together, Fiedel looped the rhythmic clangs a split second off the foundational synth melody, and made a propulsive theme that was slightly off. When he put together sheet music for the score he later found that his little mistake made the time signature of the theme into an impossible 13/16 at three plus three plus three plus two plus two. When he would complete the score for the sequel, Fiedel made things a little more plausible and used an updated 6/8 time signature.

10. SCI-FI WRITER HARLAN ELLISON WAS NOT A FAN.

After the movie was released, writer Harlan Ellison sued the makers of The Terminator for allegedly stealing the idea for the movie from two episodes of the 1960s sci-fi anthology series The Outer Limits. Ellison alleged that Cameron took the idea of two future warriors battling in the past from an episode entitled “Soldier,” and that the Terminator skeleton was taken from a similar robot design he’d created for the episode “Demon with a Glass Hand.” Rather than battling him in costly court proceedings, Orion Pictures simply settled out of court and agreed to add an “acknowledgment to the works of” credit in subsequent prints of the movie. Cameron wasn’t too happy about Orion capitulating to Ellison, mostly because he felt he came up with an original idea and any resemblance to Ellison’s work was because they both dealt with similar genre tropes. Cameron would later go on to call Ellison a “parasite who can kiss my ass.”

11. TERMINATOR 2 COST A LOT OF MONEY AT THE TIME.

When Cameron decided to revisit the story of Sarah Connor for 1991’s Terminator 2: Judgment Day, what he came up with wasn’t cheap. Its $94 million budget made it the most expensive movie ever made at the time. The sequences before the title cards allegedly cost as much money as the entire budget of the first movie. Cameron alone was paid $6 million to direct and co-write the movie, while Schwarzenegger was coaxed back into the robotic role that made him a star for a whopping $15 million salary—$12 million of which was in the shape of a Gulfstream jet purchased for the actor by the film’s producer, Mario Kassar.

12. THE PLOT FOR THE SEQUEL WAS THE ORIGINAL PLOT OF THE FIRST MOVIE.

Early story treatments for The Terminator had two Terminators sent back to our present to battle each other, but the dual robot idea ended up being too costly for the original film's relatively small budget. The initial ideas for T2 adopted the double Terminator idea, but would have had one good T-800 and one bad T-800 fighting each other, both of which were to be played by Arnold Schwarzenegger. Cameron scrapped the idea because of logistical reasons and cherry-picked another unused idea from the original film’s early story treatments for the villain: the liquid metal T-1000.

13. STAN WINSTON TECHNICALLY DIRECTED THE FIRST FOOTAGE OF T2.

Before filming on the sequel even started, Cameron had Winston direct and shoot a teaser trailer for T2 featuring an assembly line showing how the T-800s were created, and culminating in a robot in the form of Schwarzenegger uttering his famous phrase, “I’ll be back.”

14. THE MOVIE USHERED IN A NEW ERA IN SPECIAL EFFECTS.

Cameron had to leave the liquid metal T-1000 out of the original movie because it simply wasn’t possible using the special effects that were available in the early 1980s. But he had tried a then-new method called CGI to create a few scenes involving an alien water tentacle for his 1989 film, The Abyss. He then tasked the effects artists at Industrial Light and Magic to bring a photorealistic liquid metal Terminator to life for T2 using the nascent technology.

Thirty-five different ILM artists worked for six months on shots that would only equal about five minutes of screen time in the 136-minute movie. To help them create the morphing effects, they used a new piece of software developed by ILM artist John Knoll and his brother. The software was actually the very first version of Photoshop.

Stan Winston and his team also returned to create practical effects that would accent the CGI, including a photorealistic puppet of the T-1000 with a gaping hole in its head and the liquid metal Terminator splayed in half after a shotgun blast.

Fun Fact: Early concept art used singer Billy Idol’s face for the T-1000, and Cameron briefly considered him for the part until Idol broke his leg in a motorcycle accident and couldn’t complete training in time for the movie.

15. THE FILMMAKERS LOOKED EVERYWHERE FOR JOHN CONNOR.

Casting director Mali Finn searched nationwide for a boy to play the young John Connor in T2 using all the usual Hollywood casting channels, but also in some unorthodox ways. She saw hundreds of professional actors, but it was her tendency to think outside of the box that got her to see Edward Furlong. Finn had visited The Boys and Girls Club of Pasadena, where Furlong caught her eye as he was playing with other kids. When she approached the boy he was immediately standoffish, and called her “frog lips,” but was also extremely confident. Like John Connor in the movie, Furlong had never met his father and was raised by his single mother. After a few rough auditions with the completely untrained Furlong, Finn had a dialogue coach work with him to seem more natural, and Cameron eventually hired him for the part.

16. EDWARD FURLONG GREW UP A LITTLE TOO FAST.

The inexperienced actor was only 13 years old when filming began on T2, but he quickly started to go through puberty halfway through production, which caused his voice to become noticeably deeper. The change caused Cameron to have to re-record all of Furlong’s lines from the first half of the shoot in order to match his deeper voice. Luckily Cameron didn’t shoot the film chronologically so, using ADR, he was able to replace Furlong’s high-pitched, pre-pubescent voice with his new one. Also, Cameron had to complete some pickup shots at the end of production, and one was of Furlong and Hamilton standing on opposite sides of a car. But Furlong had grown so much in height that it didn’t match the shot they had completed months before, so the production had to dig a hole for the actor to stand in to appear shorter.

17. DESPITE THE CUTTING-EDGE TECHNOLOGY, CAMERON ALSO USED SOME OLD HOLLYWOOD TRICKS.

To achieve the effect of the T-1000 taking the shape of Sarah Connor during the final battle in the steel mill, Cameron didn’t use big, expensive CGI. Instead, he used actress Linda Hamilton’s twin sister Leslie to briefly appear as Sarah before the double is exposed to John as the T-1000 in disguise. Similarly, the police officer who the T-1000 takes the shape of at the mental hospital before meeting his demise was also played by twins.

18. LINDA HAMILTON GOT RIPPED TO PLAY THIS VERSION OF SARAH.

Hamilton was cast in the original Terminator because she was an everywoman, and the original script described her as “19, small and delicate features. Pretty in a flawed, accessible way. She doesn’t stop the party when she walks in, but you’d like to get to know her.” But for T2 she would subvert that description and have to become a killing machine burdened with knowing that the world will end and nobody believes her. To get her into peak physical condition, Hamilton trained with an ex-Israeli commando named Uzi Gal for three hours a day, six days a week, for four months. Onscreen she has about one percent body fat.

19. JUDGMENT DAY LOOKED VERY REAL.

To create the nuclear blast seen in Sarah’s dream of Judgment Day, the filmmakers mixed practical and CGI effects after studying hours of actual nuclear bomb test footage. Large-scale miniatures stood in for close-up shots of L.A. being destroyed, including cars being blown off the freeway and entire buildings being demolished. The miniatures were shot at high speeds and blown apart with air mortars. The wide-angle shot of the atomic shockwave was created using early Apple Macintosh software. Cameron claims actual physicists have told him the depiction of the nuclear blast in T2 is the most authentic representation of the effects of an atomic bomb.

20. PEOPLE HATED THE ORIGINAL ENDING.

Cameron shot an ending that went from Sarah and John staring at the molten metal that had just dissolved the Terminator to Hamilton in old age makeup talking into a recorder in a park in Washington D.C. about how Judgment Day had been avoided. She watches John, who she explains is now a U.S. senator, play with his daughter amongst other people in faux futuristic clothing. When shown to test audiences at screenings held at George Lucas’ Skywalker Ranch, audience reactions were grim. They didn’t like the tonal shift of seeing their badass heroine in lumpy old age makeup, and they didn’t like the implausibility of John becoming a senator. Also, this ending doesn’t take into consideration the paradox of how Sarah would meet Kyle and give birth to John if the future apocalyptic war had been prevented.

Stuck not knowing what to do about changing the ending, Cameron called Hamilton in for a session to record additional dialogue and cut it together with 45 seconds of a beginning of a take that showed the road at night leading up to the Cyberdyne Systems building from a scene earlier in the movie. Audiences loved the ambiguity of the ending but appreciated the message Cameron wrote: “If a machine, a terminator, can learn the value of human life, maybe we can too.”

21. ARNOLD CAME BACK FOR ROUND THREE … BUT AT A PRICE.

Schwarzenegger was paid $29.25 million to reprise his role as The Terminator in T3. His contract stipulated that $1.5 million of the budget should be set aside for private jets, a fully-equipped gym, deluxe hotel suites, limousines, and bodyguards for his personal benefit at all times during production. On top of that, Arnold also received 20 percent of the gross receipts on ticket sales, DVDs, TV rights, game licensing, and in-flight movie licensing on the movie worldwide.

22. THE PRODUCTION ON T3 WAS MASSIVE.

Several city blocks used during the crane chase sequence were created entirely by the production because they needed a level of destruction that wasn’t feasible if they shot on an actual street. The studio didn’t want to foot the bill for the sequence during the crane chase when the Terminator swings through an entire building facade while hanging from the crane, so Schwarzenegger put up his own money to complete the scene.

23. T3 COST EVEN MORE MONEY TO MAKE AT THE TIME.

Its production budget of $170 million made T3 the most expensive film ever made at the time. It has since been eclipsed many times over, and now stands as the 67th most expensive film ever made.

24. CHRISTIAN BALE WASN’T SUPPOSED TO PLAY JOHN CONNOR IN TERMINATOR SALVATION.

For the fourth installment of the series, actor Christian Bale was originally tapped to play the cyborg Marcus Wright (a role that eventually went to actor Sam Worthington), but he insisted on playing John Connor, a character that only appeared briefly in the original script. Bale’s demands forced the filmmakers to rewrite the script and make Bale’s Connor character a bigger part in the plot of the movie.

25. NEITHER BALE NOR SCHWARZENEGGER WERE FANS OF TERMINATOR SALVATION.

Schwarzenegger, who didn’t appear in the fourth installment of the franchise, didn’t like the movie. While promoting the upcoming chapter of the series, Terminator Genisys, he told interviewers, “I think the three that I was in all had their own little personalities and interesting storylines.” As for Salvation, Arnold said, “Thank god [I didn’t do it]. It sucked.” When asked about his contribution to the series, Bale wasn’t so happy about it either, saying, “I knew that we gave it a shot, it didn't work. I know the reasons for that. Wisdom sometimes is knowing when you have to walk away.”

Additional Sources:
The Futurist: The Life and Films of James Cameron by Rebecca Keegan

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