LOS ANGELES - He was a Dungeons & Dragons geek, and she was a Jersey girl who grew up in an old Victorian house and wrote teen fantasy novels. They (artist Tony DiTerlizzi and author Holly Black) met some six years ago and discovered a shared sensibility for all things magical. So they started a novella series about a secret world of faeries and goblins, and called their books The Spiderwick Chronicles. DiTerlizzi did the illustrations and Black came up with the story, which centers on a woman (Mary Louise Parker) who moves her three kids out to an old family manor in the wake of a divorce.

The kids soon discover their uncle left behind a field guide to the various magical creatures that inhabit the nearby forest. Because it exposes all their secrets, they have to try to keep it from getting into the hands of the evil ogre Mulgarath (Nick Nolte). Along the way, they get a little help from their friends, a brownie named Thimbletack (voiced by Martin Short) and a hobgoblin (voiced by Seth Rogen).

"They're ordinary kids in extraordinary circumstances," explains DiTerlizzi during a roundtable discussion held in Los Angeles. "They don't live in a land far, far away in a time gone by. They're dealing with an unfortunate reality in our society; their family is being torn apart by divorce."

Of the three children, Jared (Freddie Highmore), in particular, has trouble handling his father's absence and is often being scolded by his mother and getting in trouble at school.

"Jared has a lot of anger and he has to figure out how to deal with that anger," Black says. "The idea is that these creatures are among us and it's something you might see out of the corner of your eye. It's something that any kid who sees Spiderwick and goes into his backyard might think could happen to him, too."

Though it's not nearly as epic as the Harry Potter, Narnia or Lord of the Rings tomes, turning the book into a film proved to be a challenging endeavor and involved a bit of artful adaptation. The entire fourth book isn't included in the film and many of the mystical creatures don't make the cut. But the story doesn't suffer for it.

"We would be foolish to expect a series of five books, each with their own plot that connected to one overarching plot, would somehow work in a three-act structure that's 90 minutes long," DiTerlizzi says. "I think a direct facsimile of the books would have been kind of boring. We outlined the thematic elements that really meant a lot to us and told [director Mark Waters] if he could keep those intact, we'd be good. We got to see all the scripts, and where Holly and I came from was less about [the specifics] and more like, "You know you set this up in act one and it never pans out in act three.' It was more of a script doctor point of view. We make books; we don't make films. So who are we to tell them how to do their jobs?"

While he might seem like an odd choice to direct, Mark Waters (Mean Girls, Freaky Friday, Just Like Heaven) proved a good match.

"We thought Mark had a real voice, especially for teenagers," producer Mark Canton says. "I know from my end that that's an important component. You don't want them talking like some lame movie kids. They sound like real kids. You know that right from the get-go."

For Waters, who for the first time works extensively with computer-generated graphics, being able to veer from the book's structure was a bonus. And his team of Industrial Light & Magic experts helped do the trick.

"The freedom I got was because Tony and Holly were so involved from the beginning," says Waters, who first met with them while they were still finishing the series. "They gave me the freedom to make a great movie. They supported moving away from the book. They're more movie lovers than they are navel-gazers about their own work. That gave me the freedom to make a big, exciting movie and not feel like we have to be totally loyal to the books. I just want the movie to be a great time. I'm hoping that on some level, you're getting the sense that it's about the importance of family. Hopefully, they get that with the medicine hid pretty deep in the dessert."

The Spiderwick Chronicles: Opens Thursday areawide.