'Dear David' saga terrified Twitter in 2017. Director explains how the thread became a new horror film: 'I love nightmares.'

In 2017, BuzzFeed writer Adam Ellis took to Twitter to recount his encounters with a ghostly child named David. Over several months, in 140-character installments, the “Dear David” Twitter thread became a masterclass in suspense, having us refresh our feeds with bated breath.

Like Slenderman before him, David was pure digital-era folklore, shared and dissected by fear-addicted onlookers across the globe — a story engineered for social media.

Now, the meme has become a movie — in theaters, on demand and on digital now.

At the helm of David’s resurrection is Scottish director John McPhail, who says the challenges of turning viral tweets into a horror film still haunts his dreams.

“I always have nightmares. I love nightmares,” he says with a laugh. That’s because, truth be told, the horror genre has always been his favorite.

“I really like exploring trauma,” explains McPhail, who’s best known for the wild 2017 zombie musical Annie and the Apocalypse. “I think that’s what horror does amazingly. There are so many feelings you get to face yourself when you’re watching. I love going along for that ride. You’re exploring characters because they’re always flawed, and that’s where you see yourself. As a watcher, you explore that trauma with them.”

There is plenty of trauma in the screenplay by Mike Van Waes. As conceived by Van Waes, the film’s main character, Adam (played by Augustus Prew), is, like Ellis, a gay writer at BuzzFeed who berates an online troll for criticizing his work, eventually telling the antagonizer to “DIAF” (die in a fire).

As depicted in the 2017 thread, Adam then experiences a series of eerie happenings suggesting paranormal activity in his apartment — jump-started by a rocking chair suddenly rocking on its own.

Van Waes’s screenplay takes it further. Not only does the ghostly David have his own social handle, but it also creeps into other gadgets — re-downloading the hookup app Grindr on Adam’s phone to make his boyfriend think he’s cheating. Talk about scary.

The film transforms the thread into a cautionary tale about cyberbullying, revealing that David was a child who grew up during the early internet age chatting on AOL with strangers. After being told by someone to kill himself, David becomes a vengeful spirit who haunts the internet (and, apparently, hookup apps), murdering those who write mean anonymous comments.

McPhail says he was attracted to Adam as a protagonist because “you don’t see someone like him in horror films often.” The filmmaker also calls the storyline “poetic,” giving viewers a chance to not only see the ramifications of online bullying, but to also show us how we, at times, are just as bad as the bully.

Using ghosts as a metaphor for loneliness and validation wasn’t a stretch, says McPhail. Growing up, he recalls having an imaginary friend who very well may have been a ghost.

“My mom used to be terrified,” the director says. “I would go in the cupboard in the hall and talk to this little kid. I would sit there talking and my mom would be like, ‘John, who are you talking to?’ I would say, ‘It’s just my friend.’ He was a wee boy and I’d have full-blown conversations.”

Those secret chats with the wee boy helped shape McPhail’s superstitions today. “I mean, I believe in spirits,” he explains. “Everything in my life that’s taken me taking me down a path and taken me somewhere, I always kind of felt like I’ve been guided. I’ve never been forced or pushed or anything. ... I don’t believe anybody’s here to terrorize me or haunt me. But I do believe in those things.”

That belief may have even inspired his career as a filmmaker. “I love Ghostbusters,” he says of the 1984 comedy written by and starring Dan Akroyd. “I think inch-for-inch it’s utter perfection.”

To that end, even during the scariest moments of filming Dear David, McPhail says finding moments of levity always helps.

“You’re working 13-, 14-hour days, and there are grueling weeks sometimes,” he says. “The crew, the people get exhausted and tired, so when they get creeped out by scenes, it just adds fuel for us to keep going and keep pushing.”