In 1997, three actors were sent into the woods. Their story became The Blair Witch Project.

In 1999, we weren’t quite the cynics we are today. The ability to separate fact from fiction is quite literally in our pockets now; a search, swipe, scroll away.

But 20 years ago, there was a brief cultural moment in which we teetered on the edge of the internet age, a moment in which two filmmakers were able to create a horror film on a $60,000 budget which would leech into the cult movie canon and go on to rake in $250 million.

The Blair Witch Project asked us to suspend our disbelief and buy into a supernatural storyline in which a trio of documentary makers ventured into the woods near Burkittsville in the US state of Maryland to investigate a local legend. It’s their footage, found a year after they vanish, that we’re told we’re watching.

The shaky hand-held camera work. The heavy, tearful breaths of the panicked group. The haunting sounds echoing through the trees. Now iconic (and heavily parodied) movie-making moments that pioneered the found-footage genre.

But it’s not just the movie itself that meant countless viewers were prepared to believe what they saw. It’s the legend that masterminds Eduardo Sánchez and Daniel Myrick created behind it.

The same year The Blair Witch Project premiered, a program aired on US paid-TV network, The SciFi Channel, called Curse of The Blair Witch. It featured interviews, news bulletins, media clippings, to tell the story of deaths and disappearances around the town of Blair since the 18th Century. Residents, the program showed, blamed the mysteries on the ghost of Elly Kedward, a local woman accused of practising witchcraft and sentenced to death by exposure in the 1780s.

But Blair doesn’t exist, nor do the missing people. It was all fabricated; a PR masterpiece designed to lay the foundation for the feature film.

It’s not real… right?

The Blair Witch Project brought the mystery mainstream, leaving audiences unnerved and perplexed by the “it’s not real… right?” premise. In a strange way, the fact that audiences were never shown the witch seemed to give them more permission to buy into the narrative.

Instead, the fear was generated entirely by the reactions of the three stars, Heather Donahue, Michael C. Williams and Joshua Leonard, all of whom played fictionalised versions of themselves — real names, and all.

Sánchez and Myrick went to now-infamous lengths to achieve authenticity from the trio.

It started with the audition process. Myrick told Vice that once the hopeful actors signed in, they were presented with a paragraph of direction that read: “You were convicted of murder twelve years ago, and now you’re getting ready to state your case in front of the parole board.” Then, the moment they walked into the audition room, Ed Sánchez asked, “What do you have to say for yourself?” No greeting, no introductions, nothing. Anyone who hesitated was immediately ruled out.

Donahue’s response terrified the filmmakers, Myrick said: “She was the only person out of the tons of people that I saw over the course of the year, that, when asked ‘Why do you think you should be released on parole,’ she looked at me dead in the eye and said, ‘I don’t think I should be’.”

The chosen cast were then armed with cameras, GPS equipment and camping supplies, and dropped into the middle of the woods. Donahue, Leonard and Williams captured 19 hours of footage over the course of eight days, during which they had barely any face-to-face contact with those behind the scenes.

There was no script to work with. Instead, they were to left to rely on brief, daily outlines for their character, which Sánchez and Myrick left beneath milk crates at pre-plotted locations throughout the woods. The cast were instructed to keep the details from their co-stars and to remain in character as much as possible. (If they wanted to speak out of character to the crew, they would have to radio through with a code word: "bulldozer").

Their food was rationed more each day, in order to make them irritable and on-edge ("Your safety is our primary concern, but your comfort is not," producer Gregg Hale told the cast). And Sánchez and Myrick would mess with them during the night. Footage in the film of loud footsteps near their campsite and the eerie sounds of children playing were all created by the duo, without prior knowledge of the cast.

Perpetuating the Blair Witch myth.

When audiences emerged from the movie, they carried with them the hype so expertly engineered by Sánchez and Myrick.

And the internet played a big part in that.

More and more households were dialling up (remember that dial tone?), and Sánchez recognised the potential of using a website to bolster the mystery. The rudimentary page he created was littered with video interviews featuring 'surviving relatives' and case 'experts', as well as photographs of supposed police evidence. Crucially, there was also a message board in which viewers could discuss and debate the content of the film.

Of course, being pre-social media, Donahue, Leonard and Williams didn't yet have a significant online footprint. They were also kept away from media or public appearances, and the now-defunct distribution company, Artisan Entertainment, deliberately edited their IMDB pages to say they were 'deceased'.

Donahue told Broadly her mother even received sympathy cards.

So willing are some people to believe the story, she said, that "There are some people online who think that we are hired shills because those kids really did die and we've been hired to be them so that nobody will get arrested".

Where are they now?

After the film, most involved continued careers in Hollywood. Sánchez and Myrick went on to make more horror films including Solstice and The Objective, while Leonard has remained active as an actor, with roles in movies including Disney's The Shaggy Dog (2006), The Motel Life (2012), If I Stay (2014) and Unsane (2018).

Donahue too remained in the business for a while, but eventually abandoned acting to become a medical marijuana farmer. She wrote about her experience in the memoir, GrowGirl: How My Life After The Blair Witch Project Went to Pot. In interviews since, she's reflected on the damage the movie — and using her real name — did to her professionally and personally. Some people were even mad, she's said, when they realised she was, in fact, alive.

"People love the safety of horror movies, the controlled anxiety," she wrote in The Guardian. "But this one was supposed to be different. This one was supposed to be real."