BEVERLY HILLS, Calif. (AP) — In 1989, when Stephen King had already published more than 20 books, three teenagers were discovering his horror novel "It," a 1,100-page epic about a group of adolescent outcasts and a shapeshifting villain who most often manifests as a child-eating clown.
Those teenage readers grew up to become filmmakers, and they joined forces to make "It" into a movie, opening Friday. Director Andy Muschietti, screenwriter Gary Dauberman and producer Seth Grahame-Smith say King's work shaped the storytellers they are today, and his approval of their adaptation is critical if they're to consider the film a success.
"There's no way I would be a writer or a novelist without Stephen King," said Grahame-Smith, author of "Pride and Prejudice and Zombies" and "Abraham Lincoln: Vampire Hunter," both of which were adapted for the screen. "The last thing we would ever want is to be part of a lesser Stephen King movie."
"He's definitely on my Rushmore of horror writers," Dauberman said, also mentioning Edgar Allan Poe, Christopher Pike and R.L. Stine.
If King dislikes the film, "it's like disappointing a family member in a way," said the screenwriter, who counts the horror hit "Annabelle: Creation" among his credits. "And my wife's from Maine (like King), so I'm like, 'Am I going to be able to go back and visit?' He's just everywhere."
Muschietti said King is one of the greatest creative influences in his life. "I'm wired with his way of telling stories," he said.
But with "It," the filmmakers immediately made two major changes to the original novel: they chopped it in half and shifted its setting by 30 years.
"It just became evident that you can't take an 1,100-plus page book and condense it down into one movie," Grahame-Smith said.
The novel centers on seven characters in Derry, Maine, during two periods in their lives: as kids in the late 1950s, and as adults in the mid-'80s. The film, though, focuses only on their childhood, when they first meet Pennywise the Dancing Clown. And it's set around the time the filmmakers first discovered the book.
Today's moviegoers may be more nostalgic for the 1980s than the 1950s, Grahame-Smith said.
"They remember growing up and being teenagers in the 1980s, so it just made sense to push it forward," he said. "So that ultimately when we do hopefully get to tell the second part of the story, it'll be present day."
This film is about how a group of kids who call themselves "The Losers' Club" band together when they discover a mysterious and evil force is responsible for the frequent disappearance of children in their small town. One boy in the club lost his beloved little brother to it. Others have had personal encounters with the creepy being. They decide that their only chance of beating it is to stick together.
"It" stars a fine bunch of child actors, including Jaeden Lieberher ("The Book of Henry") and Finn Wolfhard ("Stranger Things"), with Bill Skarsgard as the terrifying Pennywise.
King said in an interview last week that the book is among his favorites, "in kind of a problematic way."
"There was a point in my career where people were calling me Horrormeister and, you know, the scary guy. And I thought well, fine. OK. We'll do a final exam and I will say everything there is to say that I know about monsters and fear and how childhood is the perfect growth medium for terrifying things — everything from Hansel and Gretel to the Werewolf of London — and I'll put it all in one book and that will be it, that will be done and I can move on and do whatever other things that I've got to do," King said by phone from his home in Maine. "And so for this to come back at this time is kind of a remarkable thing."
King would go on to write many other horror stories, including "Misery" and "The Tommyknockers," both of which were adapted for the screen.
He said he has no problem with the 1980s setting for "It" because "there's the same feeling of nostalgia for people who are grown-ups who say, 'Well, I remember that era.'" And he thinks it was a "no-brainer" to split the book in two and focus just on the protagonists as kids.
"I thought it was a terrific idea," he said. "And I'm hoping that the movie will be a success and they'll do the grown-ups, and then they can do a DVD package where everything's together!"
Summing up his thoughts on the film, King said, "I liked it."
"That was when I exhaled," Dauberman said. "I want everyone to enjoy it, but his opinion was the one that mattered to me most."
The same goes for the director and producers.
"In some ways, the best day of this whole experience was when we screened the movie for him and he loved it," Grahame-Smith said. "After that, it was a huge sigh of relief because whatever else happened, we pleased the man himself."
Follow AP Entertainment Writer Sandy Cohen at www.twitter.com/APSandy .