In the 1970s, when horror movies started to get more and more extreme, it wasn’t just the blood and the savagery that increased. So did the sensation that you were seeing something “real” — not mere “horror-movie violence” but violence as it really was, in all its existential terror. It was Hitchcock’s “Psycho,” in 1960, that sounded the original slasher chord of that era, but the event that truly ignited the reality-horror revolution was the Manson murders. They set off such a gruesome shock wave in the culture that they turned into a kind of movie of the mind, a psychotic nightmare made flesh. The slasher films of the ’70s channeled the Manson mystique — notably “The Texas Chain Saw Massacre,” which presented itself as a true story and served up its spectacle of slaughter with a documentary grittiness.

After a while, all of this began to feed an addiction on the part of the audience. Having gorged on films like “Texas Chain Saw” and “The Last House on the Left,” horror fans wanted a higher high, a bloodier bloodbath. They wanted a horror movie so extreme that it could touch reality itself. Inevitably, what horror fans — or at least some of them — began to crave was actual horror. They wanted to witness, right there on film, the kinds of unspeakable crimes that even the most extreme horror movies merely staged.

In 1978, the mondo horror exploitation film “Faces of Death” came along to feed that appetite. It presented itself as a documentary (and, in fact, contained snippets of documentary footage); it implied that you were watching actual scenes of human beings and animals being tortured and killed. The truth? “Faces of Death” was almost entirely a fake. The “real” murders it depicted were staged movie murders presented in grimy nonfiction drag. But the film tapped into something. It grossed $35 million internationally (an impressive sum for 1978), and it went on to become a major cult curio of the VHS era. In a way, it was ahead of its time. It presaged the hunger for seeing the forbidden with your own eyes that is now fed on a daily basis by the Internet.  

The new “Faces of Death” feels, at times, like it could have come right out of the grindhouse ’70s. But it’s not a remake or another fake documentary. It’s a halfway clever retro slasher movie that, as directed and co-written by Daniel Goldhaber (“How to Blow Up a Pipeline”), actually has something on its mind. It’s a B-movie meditation on the original “Faces of Death,” featuring a mad killer who is restaging — and posting online — a series of murders and executions from the earlier film.

But he’s doing it with a meta media consciousness, turning homicide into the ultimate clickbait. He’s saying, “Admit it! This is what you want.” And when you consider the kinds of things that people now spend their time seeking out online, you can’t say that he’s wrong. “Faces of Death” was made for the era in which Hillary Clinton, in her Congressional deposition on the Epstein files, was actually asked about Frazzledrip, the urban legend of a video file (it was found, at least according to the legend, on Anthony Weiner’s laptop) that depicts…well, I’m not even going to say. Look up the legend yourself (but you probably already have).

Margot (Barbie Ferreira), the heroine of “Faces of Death,” is a shy Zoomer who works as a content moderator for a website called Kino that’s a viral shopping mall of transgressive video. Her job is to separate the real from the fake, the just-forbidden-enough-to-be-titillating from the too-taboo-to-post, and to flag content that goes over the line (though given what doesn’t go over the line, it’s a little hard to tell what the criteria is). Margot is played by Barbie Ferreira, the gifted actor from “Euphoria” and “Bob Trevino Likes It,” who brings the character a winsome insecurity that makes her more distinctive than the usual final girl.

The main reason that Margot is so skittish is she’s still reeling from a slice of video infamy in her own past: She was part of a train-track stunt in which her sister was killed, right on camera. And this has lent Margot a debased sort of celebrity. She likes to hide away in her corporate cubicle, where lately, on the job, she’s been seeing underground videos of ritualized death (a gruesome electrocution; a man with his head through a table being beaten by hammers — and then his brains get eaten) that look real but might be fake. Are they connected? It’s through her roommate, the queer horror buff Ryan (Aaron Holliday, who’s like the second coming of Taylor Negron), that she discovers the original “Faces of Death,” and learns that the murders she’s been seeing are copycat versions of the ones in that film.    

We know the new murders are real, because we’ve been following the stealth moves of the killer, Arthur (Dacre Montgomery), who kidnaps third-rate celebrities — an obnoxious influencer (Josie Totah), a local news anchor (Kurt Yue) — and places them in cages in the basement of his faux-grand cookie-cutter Florida suburban home, where they’ll wait their turn to be featured in one of his viral snuff films. Dacre Montgomery has an aristocratic baby face, and his Arthur is good at putting on personalities: the geek, the righteous neighbor who’s been trespassed. He wears an eerie white death mask when he’s doing the kidnapping, and a stocking mask when he’s doing the killing. But he’s most interesting when he makes a speech about the taboo-video industrial complex. He explains that the Internet loves him; that gun manufacturers love him (because people want to protect their homes); that the government loves him (because more paranoia means more control). To use the film’s invocation of an old cliché, he’s “giving the people what they want.”

That a sicko like Arthur isn’t just a serial killer — he’s part of the new anything-goes attention economy! — is a notion that’s provocative in a facile way. Yet that’s part of what gives “Faces of Death” the interesting texture of an old grindhouse movie; they often had ideas too. “Faces of Death” is “ambitious” trash, with the courage of its own gaudy thematic grandiloquence. (It’s the only movie I’ve seen where the publicity material contains a folder of “Censored Posters,” for that transgressive marketing effect.) The whole allure of staring death in the face on film wasn’t born in the ’70s, of course. It goes all the way back to movies like “Frankenstein” and “The Mummy.” But “Faces of Death” taps into a creepy 21st-century voyeurism: the pornography of death. That’s what the 1978 “Faces of Death” was really about — our desire to glimpse something so forbidden that it felt uncanny. We call it horror, but that word, in a way, is misplaced. What we’re really looking for is awe.