Every story, as movie trailers never tire of informing us, has a beginning. The story of the cover-song trend in movie trailers began nine years ago, when the veteran trailer editor Mark Woollen found himself grappling with a difficult assignment. This was not unusual for Woollen, who is known for producing iconic, inventive mood-piece trailers for tough-to-market, tougher-to-summarize films by such directors as Terrence Malick, Steven Soderbergh, Michel Gondry, and Alejandro González Iñárritu. The brilliantly odd trailer for the Coen brothers’ “A Serious Man,” punctuated by a rhythmically recurring shot of Fred Melamed bouncing Michael Stuhlbarg’s head off a chalkboard? That was Woollen. The trailer for Todd Field’s “Little Children,” which used the sound of an oncoming train in lieu of music? That was Woollen, too. There are some films that can’t be marketed by traditional means; Woollen is the trailer auteur to whom auteurs turn for a nontraditional solution.

In early 2010, Woollen’s company, Mark Woollen & Associates, was tapped to produce a trailer for David Fincher’s “The Social Network.” As Woollen remembers it, it was March or April; Fincher was still busy in the editing room, and Trent Reznor and Atticus Ross had not yet written the movie’s score (which would win an Academy Award). With the Cambridge Analytica scandal and the election of 2016 still years away, the Facebook story seemed like curiously dry material for Fincher, the director of “Fight Club.” “It was kind of getting beat up in the press,” Woollen said. “Like, ‘How can you make a movie about Facebook? Are you gonna make a movie about eBay or Amazon next?’ ”

At first, Woollen wasn’t sure how to cut a trailer for a Facebook movie, either. But the answer turned out to be sitting on his hard drive. A few years earlier, while searching for something else, he’d downloaded an MP3 file from what he described as “some GeoCities-looking kind of Web site.” The file was a 2001 live recording of the song “Creep”—the first hit single by the British art-rock band Radiohead—as performed by Scala and Kolacny Brothers, a two-hundred-member girls’ choir from Belgium. The recording had a lot of the things that a trailer editor looks for in a piece of music. “It has this gentle introduction, it has moments that build and swell and rise, and then it can come down and land nicely,” Woollen said. “I felt, like, Here’s a track I can build a piece around.”

More important, the music seemed to work on a thematic level. Woollen, who was not a Facebook user, had been kicking around ideas about connectivity and loneliness. He played the choir recording on repeat while driving to work and thought about “lost, lonely voices that felt like they were speaking from the depths of the Internet.” In his business, Woollen said, “You’re always talking about trailers that invite you in, saying, ‘Come and see us, come and see us.’ ” He liked the counterintuitive notion of building a trailer around a song whose refrain is “What the hell am I doing here / I don’t belong here.” “The irresistible ingredient,” Woollen said, “was one hundred Belgian girls singing ‘You’re so fucking special’ in full voice.”

The finished trailer is an unsettling masterpiece. For fifty seconds, it plays like an ad for Facebook—a montage of photos, status updates, and unseen hands confirming friendships with the click of a blue-and-white button. Then, at the one-minute mark, a pixelated image of Jesse Eisenberg’s alarmingly dead-eyed Mark Zuckerberg fades into view. Woollen said that he was nervous about showing Fincher a cut that held back the director’s own footage in favor of stock photos and family pictures supplied by the staff of Mark Woollen & Associates. But Fincher liked it; the first time he screened “The Social Network” for the studio, he played Woollen’s trailer first.

The trailer instantly turned Scala and Kolacny Brothers into the most famous Belgian girls’ choir the world had ever heard. “They played Coachella, they played South by Southwest,” Woollen said. “They had their moment.” They also licensed songs to more than a few other movie trailers, television shows, and commercials—that was them, in 2012, singing Metallica’s “Nothing Else Matters” in a trailer for Kathryn Bigelow’s “Zero Dark Thirty.”

If you screen Woollen’s best-known work on YouTube, it’s obvious how he’s influenced the way that movie trailers look. But his “Social Network” trailer quickly became a profound influence on how movie trailers sound. The auditory signature of the modern movie trailer is a deliberately eerie cover version of a recognizable pop song, usually sung at a dramatically slower tempo, often by a breathy female vocalist whose delivery suggests a ghost beckoning a living playmate from the far end of a haunted-house hallway. The production of custom-tailored, trailer-ready, high-drama cover songs has become a cottage industry.

Although a song that accompanies the action in a popular trailer can reach millions of listeners on YouTube, most of these covers never end up on any soundtrack album, let alone in an actual film. But they are the signature movie-music form produced by Hollywood’s era of perpetual reboot: riffs on preëxisting intellectual property conceived solely to promote movies that also tend to be riffs on preëxisting intellectual property. The pop cover conveys two very different promises that a blockbuster-movie trailer has to make inside of an M.P.A.A.-mandated two minutes or less: that this movie will be (a) intense and dark and modern and unlike anything that we’ve ever seen before and (b) that it won’t be too unlike what we’ve seen before, that ultimately we’ll walk away having got whatever spiritual comfort we’re looking for by buying a ticket to another movie about Lara Croft or Godzilla.

Sometimes these covers are meant to generate the same ironic tension between sound and image that Woollen found by juxtaposing Thom Yorke’s disaffected lyrics, a choir of young Belgians, and Jesse Eisenberg’s face. Think of the way that foreboding reworkings of Louis Armstrong’s “What a Wonderful World” have soundtracked trailers for movies about teen-agers fleeing futuristic dystopias (“Insurgent”) and a world rendered increasingly un-wonderful by freak weather events (“Geostorm”), or the elbowing use that the trailer for Baz Luhrmann’s “The Great Gatsby” made of the Turtles’s “Happy Together.”