Ryan Gosling as K in in “Blade Runner 2049.” ( Alcon Entertainment/Warner Bros. Pictures)

The first trailer for “Blade Runner 2049” was filled with familiar imagery from Ridley Scott’s original 1982 film — giant neon advertisements, a smoggy noirish future . . . Harrison Ford. But it wouldn’t have been nearly as potent a nostalgia injection if it hadn’t been all bathed in the old film’s warm, buzzy, synthesizer hymn by Vangelis.

The Greek composer, 74, wasn’t asked to score the sequel — that job fell to Hans Zimmer and Benjamin Wallfisch, who co-composed a score with traces of Vangelis for the summer’s “Dunkirk.” But he said he would have turned it down regardless.

“Ridley is not the director,” he said in an interview last year. “In case I could have done it, it should have been with Ridley. I hope that this film is going to be very, very good, but I knew it instinctively that this is done for me.”

Still, Vangelis’s musical shadow looms over the new film. The glacial synth chords that opened the 1982 film are as iconic as the fiery, dystopian effects they accompanied, the jazz noir love theme as integral to the experience as Scott’s visual composition — perhaps even more, according to the director.

“Fundamentally, in a sentence, I’ll say he was the soul of the movie,” Scott said.

Gosling in “Blade Runner 2049.” (Stephen Vaughan/Warner Bros. Pictures)

The director had seen “Chariots of Fire,” which won four Oscars in 1982, including for its score. Its main theme summited the Billboard charts and became an uber-popular — if eventually somewhat campy — anthem for running, and one of the most famous tunes written for a movie.

“I liked the film,” Scott said, “but I also loved the music. [It] was so off-piste, as it were, if you ski — I’m not a skier, sounds pretentious — but it was so off the idea of a pre- Second World War Olympic Games film. It was off the mark, but worked like a son of a bitch.”

After cutting his science-fiction film all day, Scott would sit with Vangelis every night until 1 a.m. at the composer’s studio behind Marble Arch in London.

“He played me the opening music of ‘Blade Runner,’ and, honestly my hairs stood on end, and from that moment on I knew I was in good shape,” Scott said.

Vangelis is synonymous with synths, and he treats his machines like a symphony — writing sweeping, melodic statements and drenching it all in reverb like an organ in a cathedral. He developed his own setup that allows him to perform multiple voices at once, and prefers to record entire, multilayered pieces in one pass.

“I don’t want to involve any thought, any personal opinion,” he said. “And this is because I prefer to have the music as pure as possible. . . . Maybe it sounds weird, but my connection with music is really different from other people. I’m not saying it’s better, but it’s definitely different.”

“Blade Runner” was poorly received when it opened, and soon the orchestra-imitating synths of Vangelis became passé. He went on to score “1492: Conquest of Paradise” for Scott in 1992, and Oliver Stone’s “Alexander” in 2004, but mostly left cinema behind. In recent years, he’s composed music for live theater and projects for NASA — his 2016 concept album “Rosetta,” inspired by the space probe mission of the same name, received a Grammy Award nomination. He’s currently composing music for London’s Royal Ballet.

For many, “Blade Runner” remains his high watermark, and its influence can be felt in the recent wave of retro-synth scores for everything from the Netflix series “Stranger Things” to “Dunkirk.” Director Denis Villeneuve initially hired his “Sicario” and “Arrival” composer, Jóhann Jóhannsson, to score “Blade Runner 2049,” but for mysterious, undisclosed reasons, dropped him over the summer in favor of Zimmer and Wallfisch.

Ridley Scott might have hired Zimmer to score “Blade Runner” had he made it a few years later. Scott collaborated with the young German composer on “Black Rain” in 1989, and continued to use him on “Gladiator,” “Black Hawk Down” and several other movies. Zimmer, 60, was a natural choice for “2049,”not only as the reigning king of blockbusters, but as a lifelong synth enthusiast whose career and style rode in on the wake of Vangelis.

Wallfisch, 38, is a classically trained English protege of Zimmer’s, and he approached “2049” with the wide-eyed reverence of someone who first saw “Blade Runner” as a boy on a “dodgy” VHS tape.

“So much of the feeling of ‘Blade Runner’ comes from that Vangelis score,” he said. “There’s an incredible scale to the sonic of [his] music, which is always overwhelming and very powerful in the way that an orchestra can be — but it’s one man performing, and there’s a sort of singularity of thought.”

Zimmer and Wallfisch only quoted an actual Vangelis motif once in the score, but they rooted the music in his vintage synthesizer palette.

Wallfisch said the question became: “How do we create the same sonic and emotional impact that came from those extraordinary, groundbreaking sounds and the method of scoring, but still reinvent and do something fresh that serves this particular story — and that feels like it’s 30 years later?”

To distinguish their sound world, the composers played with new ingredients such as low, monklike male vocals, acoustic double basses playing at the very top of their register and deconstructing and electronically reassembling the tones of a piano.

“This idea of ‘more human than human,’ that’s a central idea of what a replicant is,” Wallfisch said. “One way of trying to capture that, musically, was taking something familiar and human, and rebuilding it into something which is almost human.”

Vangelis’s dreamy, cosmic score was the sound of the future in 1982. Now, ironically, it’s the sound of nostalgia. Like a replicant, his synths were mechanical imitations of an organic orchestra — but, as Scott noted, they gave “Blade Runner” its soul.

“He just had this touch of magic,” Scott said. “I think Vangelis doesn’t age, really. That’s the trick. It’s like a great painting. You can go and look at it every bloody morning and it’s still fresh.”