Three-quarters of the way through the tape of an interview with filmmakers Daniel Myrick and Eduardo Sanchez, the sound inexplicably goes dead. The audio simply fades out and then, five minutes later, just as suddenly fades back in.

It would be unjournalistic to ascribe this technological glitch to supernatural phenomena (the batteries were fresh and the machine was otherwise functioning properly). Still, one might be forgiven for thinking such irrational thoughts when the topic of conversation is the spooky new horror film "The Blair Witch Project."

Myrick and Sanchez's commercial writing, directing and editing debut--passed off as the true story of the 1994 disappearance of three Montgomery College film students while documenting a local legend of witchcraft in the woods of suburban Maryland--first worked its disturbing magic on audiences at this year's Sundance Film Festival. A mere 24 hours after the first of four sold-out screenings, the film was picked up for distribution by a slavering Artisan Entertainment for a sum reported to be in the low seven figures.

Not a bad return for film that, Sanchez jokes, "cost about as much as a new Ford Taurus with all the options."

"The Blair Witch Project," which opens here Friday, has in six short months become one of the most anticipated summer releases among connoisseurs of the creepy, as much for the elaborate mythology surrounding the film's creation as for its boo-ability.

Part of the reason for the buzz is the film's unsettlingly realistic style. Alternating between grainy black-and-white film stock and color video footage (all of it shot by shaky, hand-held cameras and much of it in the middle of the night), "Witch" presents itself as the painstaking reconstruction of a school project left unfinished by a trio of naive kids (Heather Donahue, Michael Williams and Joshua Leonard). One day, we are told, they vanished without a trace and are now presumed dead.

When an eight-minute trailer for the film was shown in 1997 on "Split Screen," indie guru John Pierson's Independent Film Channel program, it was presented as fact, not fiction. Completely taken in by the trailer's elaborate verisimilitude, some viewers grew irate when subsequent rumors circulated on the Internet that there was more behind the making of "Witch" than Myrick and Sanchez were letting on.

"The discussion turned from a discussion of the merits of the film to a moral issue," Myrick says. "Was it a hoax? Are we fooling people? It kind of marginalized what we're trying to do."

In October of 1994, three student filmmakers disappeared in the woods near Burkittsville, Maryland while shooting a documentary.

A year later their footage was found.

With these stark on-screen titles, "The Blair Witch Project" begins. No credits, no cast list, no Directed by So-and-So. Until the end, when acknowledgments for such jobs as "Sound Mix" and "Scenic Art" roll by, its 87 low-tech minutes are almost, admits Myrick, "like watching a snuff film."

So what are he and Sanchez, friends and collaborators since film school at Central Florida University in the early '90s, doing over coffee and Coca-Cola at the Jefferson Hotel? Well, letting the cat out of the bag, for one thing.

"The line we're kind of walking is: How much do we tell people about how we did the film?" says Sanchez, a tall, dark and laid-back 30-year-old who grew up in Montgomery County. "Because how we did the film is kind of interesting. But does knowing it ruin the effect of the film? I don't know."

His partner, a 35-year-old Sarasotan, is less equivocal. "I think if I had to choose," says Myrick, who is shorter, fair-haired and more intense than his collaborator, "if I had to say, 'I want this person to see the film one way,' I would want them to get the full frontal assault of 'Blair Witch,' and only then let them read the credits at the end and let them off the hook."

He continues, "But the only way we could legitimately do that is to lie to everybody and say, 'It's all real,' and we're not prepared to do that because of the backlash."

(Note to purists who prefer their cinema straight up: Stop reading here because, like TV's "Masked Magician" specials, Myrick and Sanchez are about to give away trade secrets.)

According to the filmmakers, the trick of scaring the bejesus out of you in "Witch" is not done with the film equivalent of smoke and mirrors, as in most special-effect pictures, but by good old-fashioned campfire storytelling and bogymen. Except in this case, the campfire crew (represented by Donahue, Williams and Leonard) was equipped with a Hi-8 camcorder, a film camera and a digital audio tape machine, and the bogymen (in the persons of Myrick and Sanchez) were armed with camouflage gear, two-way radios and global positioning system (GPS) handsets.

"In the contracts the actors signed, we told them we were going to scare them," explains Myrick. "We told them, 'Don't sign this if you have any heart problems, because we're going to subject you to psychological techniques that are used in a lot of military scenarios--you know, immersive scenarios.' It was a survival school approach."

After an initial few days of filmmaking boot camp, where the cast was given rudimentary instruction in the use of the equipment, the directors sent Donahue, Williams and Leonard on a six-day camping trip into the woods of Gaithersburg's Seneca Creek State Park, a few minutes away from the Sanchez family home. Guiding them to predetermined checkpoints by means of GPS and written instructions left with the cast's daily deliveries of fresh batteries, tape and film, Myrick and Sanchez regularly ambushed the talent with nocturnal disturbances, strange rock piles constructed in the middle of the night and talismanic stickmen hanging from trees.

From more than 20 hours of improvised dialogue (most of which, says Myrick, "is boring as hell"), the story was condensed and shaped into a taut tale of personal disintegration and the paranormal, based on Myrick and Sanchez's meticulously pre-plotted outline.

Even though their actors were deliberately being frightened and were often cold, hungry, wet and irritable, Sanchez believes that the cast did not have it as bad as the filmmakers. "They probably slept more than we did," he laughs. "For us it was just constantly charging batteries and stuff and trying to stay one step ahead of them. Once we woke them up and they did what they had to do, they could go back to sleep."

The immediacy and honesty of their reactions were exactly what Myrick and Sanchez were looking for.

What seems like amateurish, occasionally out-of-focus footage taken by inexperienced and very scared filmmakers lost in the woods is actually amateurish, occasionally out-of-focus footage taken by actors playing inexperienced and very scared filmmakers lost in the woods. Although they were never more than a radio call away from safety, at times the frustration, fear and confusion on the faces of Donahue, Williams and Leonard are all too believable, and not just because their directors were gradually cutting back on the daily food rations they left with each day's acting notes and supplies.

There is one scene in particular, when the trio are seen running through a pitch-black forest at night, in a jumble of chaotic terror accompanied only by the swaying light of the camera lamp, confused frantic footfalls and heavy breathing.

Although the route they were to run through a dry creek bed had been mapped out during the day and all obstacles had been removed to avoid injury, Donahue suddenly catches a glimpse of something in passing that she had not expected to encounter.

"What the [expletive] is that?" the actress screams, in a bloodcurdling voice so full of spontaneous dread her reaction couldn't have been faked. The audience, of course, sees nothing.

So what was that?

"That was me." The answer comes from a slightly built young man who has been sitting quietly throughout the interview in an adjacent booth.

"Yeah, that was Rick [Moreno]," explains Myrick, "our art director and ghost guy.

"We dressed Rick in white long johns, put a white stocking on his head and white socks on his hands and over his shoes, and set him in the woods just as Heather would be running by. He was trusting it was going to read on film because we were originally going to freeze the frame on this thing and zoom in on it like on one of those old 'In Search Of' episodes."

Obviously, then, Myrick and Sanchez realized that would be a bit too heavy-handed, right?

They must have come to their senses and realized it would be far scarier if the audience were left to imagine what it was Donahue saw.

"No, that wasn't it," laughs Myrick. "It just never read. We even reshot the scene ourselves like we were holding the camera a couple of times to make sure it read, you know. We looked at every take, frame for frame, and it just amazed us that it didn't read at all. We tried all sorts of distances."

"Nothing came out," adds Sanchez, shaking his head half in amusement, half in amazement. "Not even a hint. It was like he was a real ghost."

BEHIND THE 'BLAIR WITCH PROJECT'

Daniel Myrick and Eduardo Sanchez went to great lengths to fabricate a 200-year-old back story leading up to the modern-day events depicted in "The Blair Witch Project," including the creation of a dogeared "1809" publication called "The Cult of the Blair Witch" and distressed-looking newsreel footage about a series of 1940s murders that were attributed to the witch's influence. To further explore the elaborate mythology behind the film, visit the Web site www.blairwitch.com or watch the Sci-Fi Channel special "The Curse of the Blair Witch" tomorrow at 10 p.m.

CAPTION: Eduardo Sanchez, left, and Daniel Myrick, whose "Blair Witch Project" opens Friday.

CAPTION: "The line we're kind of walking is: How much do we tell people about how we did the film?" says Eduardo Sanchez, left, with Daniel Myrick.