Scary Stories to Tell in the Dark is not an obvious movie. Guillermo del Toro explains how they adapted it.

The anthology Scary Stories to Tell in the Dark was a cornerstone book series for an entire generation of horror fans. Even if you couldn't make it through all of author Alvin Schwartz' short stories, illustrator Stephen Gammell married perfectly unsettling images to some of the most famous ones, that have lingered -- and lasted -- for decades.

On August 9, director Andre Ovredal (The Autopsy of Jane Doe) will release an adaptation of the series in conjunction with producer Guillermo del Toro and screenwriters Dan and Kevin Hageman, who wove together those stories into a rich and terrifying tapestry that pays tribute to the source material while introducing its legacy to a completely new audience.

Del Toro and Ovredal hosted an event Thursday in Los Angeles where they not only unveiled a new theatrical trailer for the film but showed guests a clip that hints at the terror that awaits audiences on August 9. Del Toro explained his longtime affection for the book series and what resonated with him about the material. "I basically was roaming through a bookstore in San Antonio, Texas, in my early teens and I came upon this volume that had an irresistible title, Scary Stories to Tell in the Dark," he said. "The cover illustration was so creepy and I started browsing it. And the telling of the tales was incredibly efficient, lean and mean. It really was like having a campfire between those two covers."

"The beauty about the book is that each story is self-contained, but that's the nightmare of adapting it and making it into a film," del Toro continued. "So I had to come up with a concept that encompassed a theme. And what we did is we tried to find a period of time in which stories affected everyone — who we were as humans, and even as a nation at that moment. And we started to very carefully lay down the pieces to make it thematically relevant to the stories we were telling."

Del Toro was rumored as the director of this project a few years back, but as seems to happen often with the Oscar winner, he got busy with other things and the timing threatened to undercut his ability to work on it at all. "The challenge was to find the filmmaker that could do this," he said. "When I produce, I'm in the corner, but the guy getting the punches is the director. So I had to go with somebody that I greatly admired. And it just so happened that Andre and I had communicated when he came up with a movie called Troll Hunters, which I loved, and then The Autopsy of Jane Doe, which I was praising as much as I could through Twitter, and we started corresponding."

"He was the one and only filmmaker we approached," del Toro revealed. "And fortunately for me, he accepted."

Norwegian-born Ovredal said he was unfamiliar with the books when de Toro tapped him to direct, but thrilled at the chance to work with a bona fide legend at his side, and quickly discovered ideas that resonated with him.

"I'm just in awe of being able to work with Guillermo," Ovredal said. "I've learned so much about filmmaking from a storytelling point of view, from how to direct actors, how to shoot a movie, everything. But I didn't know about these books, and I fell in love with the screenplay that [Guillermo], Kevin, and Dan created, which was just this kind of Amblin-esque scary movie set in a period that was so exciting. And it was just a unique opportunity to create both a fascinating image of America in the '60s as well as a really wonderful story about these characters."

Ovredal then showed a scene from the film based on the story "The Big Toe," about a young man who discovers that he has inadvertently come into the possession of the severed digit of a zombie who is determined to get it back. In the scene, Auggie Hilderbrandt (Gabriel Rush) is learning from two of his friends, Stella (Zoe Colletti) and Ramon (Michael Garza), that a book they discovered is writing its own stories — and they're wreaking havoc on their very real lives.

Auggie unwittingly becomes that zombie's pursuer, hiding under a bed as the creature, directly inspired by that wonderful art by Gammell, lumbers through the house. Ovredal's camera carefully scans the space in Auggie's house, creating a palpable sense of dread and encouraging the audience to lean closer to find out what happens as he tries to evade detection by this terrifying creature.

Credit: CBS Films

Afterward, Ovredal and del Toro introduced the film's young cast, including Rush, Colletti, Garza, Austin Abrams, Austin Zajur, and Natalie Ganzhorn. "It was such a wonderful, wonderful story," said Ovredal about the script created by the screenwriters. Del Toro explained the process of choosing and assembling the stories. "We did American Idol with the stories in the writers' room," he joked. "We distilled it to the five or six that we liked the most. Some of them are told in their entirety, some others are referenced. Those that know the books will see more than people that haven't read the book. But we basically distilled it to the ones that everybody seems to remember the most."

As the event came to a close, del Toro and Ovredal fielded a few questions from the audience. What was clear was that many of the guests knew the source material well — they had grown up with it, and were now passing it on to their own children. How would the film complement that passing of the torch? Del Toro indicated that he was most eager to share this both with that established readership that, like himself, had thrilled from a young age at the stories, as well as moviegoers unfamiliar with the material, young and old, who liked to be scared. "I wanted to have standees that said, 'You have to be this tall to see this movie,' but somebody beat us to it," said del Toro.

"The idea is that the books are favorites amongst young readers. And I think that there are two or three generations of parents that know the books. So it's not an unknown," he observed. "They know that this is a roller coaster. It has a sense of fun and as a really a throwback, wholesome feeling, but it's also scary. So it's really a ride, but there is a safety bar in it."

Scary Stories to Tell in the Dark arrives in theaters on August 9.