Don’t look now. While studios have been busy hyping a receding wave of torture-themed horror films — namely the “Saw” and “Hostel” franchises, as well as overbaked remakes of classics such as “Halloween” and “The Hills Have Eyes” — the horror genre is quietly experiencing a resurgence of its low-budget, high-anxiety, 1970s vitality.

One sure sign is the return of zombie auteur George A. Romero, whose seminal 1968 shocker “Night of the Living Dead” was a template for the contemporary horror film as social allegory: Behind its drive-in chills was a parable about a nation eating itself alive in the shadows of the Vietnam War.

“The thing about the late 1960s, and guys like me and Tobe Hooper [‘The Texas Chainsaw Massacre’] and Wes Craven [‘Last House on the Left’] was the anger that we had,” Mr. Romero said recently. “We showed a face. We showed our political viewpoint. We said, ‘this is what we’re angry about.’ But being angry doesn’t mean you go out and do something cruel. In a way, that’s terrorism.”

Mr. Romero, whose “Diary of the Dead” opens today and takes the viral motif of his zombie saga into the virtual age of MySpace and YouTube, is dismissive of “horror-porn” and its claims to reflect a violent world — or at least the excesses of Guantanamo Bay and Abu Ghraib. “Maybe I’m just an old-fashioned cat,” the 68-year-old New York native said, “but I just don’t get it.”

Rather than drop hints or scrape the surface of reality, “Diary of the Dead” is bracingly explicit in its commentary. Images from the aftermath of Hurricane Katrina are mixed into a montage of news footage, and the leader of a group of heavily armed black survivors of the zombie plague relishes his sudden empowerment. “We’re finally in charge,” he declares. “All the people without tans went away.” Meanwhile, the zombies themselves become objects of passive torment: A harrowing final shot evokes the real-life inhumanity of Abu Ghraib to a graphic extreme.

Mr. Romero’s film takes the form of a documentary made by a group of Pennsylvania film students during an apocalyptic outbreak of zombie attacks. Most of the shots are seen through point-of-view camera frames, surveillance cameras, and computer video downloads. It’s become a popular concept of late, and not solely in low-budget horror films such as “Diary” or the “Blair Witch”-inspired indie film “The Poughkeepsie Tapes,” which opens later this year. Movies as wildly disparate as “Cloverfield,” Brian DePalma’s “Redacted,” and the forthcoming “Vantage Point,” about an attempted presidential assassination seen from multiple video cameras, make it a structuring element.

“We thought that we were being innovative,” Mr. Romero said of his stylistic instincts. “Now all of a sudden we’re trendy.” Brothers John and Drew Dowdle, whose “Poughkeepsie Tapes” puts a cheap video camera in the hands of a serial killer with a flair for drama, won a Hollywood gig for their point-of-view skills. The pair is finishing an American remake of the prize-winning Spanish horror film “[REC],” which follows a reality-show news reporter and her cameraman into an apartment building whose residents have been acting strangely — so strangely, in fact, that the structure is sealed off to prevent anyone from escaping. Then really terrible things happen, all captured on digital videotape in dingy lighting.

The original film, shot in Barcelona by Jaume Balagueró and Paco Plaza, boasts some of the sharpest “jump-scare” scenes in recent memory (just type the movie’s title into YouTube.com and grab some popcorn). Yet its grip derives not solely from zombie cliché, but rather from the imaginative handheld camera work that reinforces the eerie viability of the situation: It looks so real, it must be real. It also helps that the film indulges in the disarming humor of a softball reality episode gone brutally haywire.

“A lot of what’s scary about a horror film comes from rooting things in perspective,” John Dowdle said. “As long as you’re not cutting wide so the audience can see everything, something may be coming from behind you.” Drew Dowdle, joining his brother on a conference call from their Los Angeles office, chimed in: “It’s exciting not to see what you want to see.” The Dowdles, both in their early 30s, were in post-production for “Quarantine,” their remake of “[REC],” which will be released this fall. “It’s fun,” John said, referencing Michael Powell’s 1960 cine-stalker classic “Peeping Tom” as perhaps the first point-of-view horror film “to make the camera a character.”

The perspective flips in “The Signal,” opening next Friday, in which flat-panel televisions begin emitting a mysterious, staticky Rorschach Blot transmission that turns a city of couch potatoes into rampaging homicidal maniacs. Shot for almost nothing on a $10,000 Canon HD video camera by a trio of Atlanta filmmakers, the movie opens with an homage to “Last House” and “Chainsaw Massacre” before unspooling as a three-part story in which each new segment is seen from a different corner of a love triangle. At the risk of divulging too many details, it’s important to note that the film’s tone shifts radically as each new director takes over his section: What begins as a mash-up of Romero, early David Cronenberg, and a little bit of J-Horror technophobia segues into morbid slapstick that would tickle Stuart Gordon (“Re-Animator”), before veering into psychotropic weirdness. “You could use the same conceit for a science-fiction film or an apocalypse story,” one of the directors of “The Signal,” Jacob Gentry, said. The effort evolved from several years of experimental film workshops staged with actors from Atlanta’s Push Push theater troupe. What began as an exercise in the surrealist game “the exquisite corpse” turned into something “like a David Lynch movie, like ‘Twin Peaks,'” Mr. Gentry said. “But it was an organic process. We didn’t want it to look like a gimmick.”

What seems novel, besides the sudden shifts in tone, is the self-analytic regard of the victims deranged by the titular signal. That, and the fact that just about everyone in the film “has the crazy,” to use the screenplay’s lingo — perhaps a nod to Mr. Romero’s half-forgotten “Living Dead” followup, “The Crazies.” “The idea is that it’s happening to everybody,” Mr. Gentry said. “No one is immune, and therefore everybody has to deal with it.”

When Mr. Romero talked about his fascination with viral culture, it had a disarmingly familiar ring. “I wanted to do something about the blogosphere and all the craziness of people being captured by it,” he said. “There could be a million Hitlers out there, and if they could make themselves credible, they’d have a million followers — a million people drinking the Kool-Aid.”