ATLANTA -- Brendan Fraser has discovered he's done dads a favor by making "Journey to the Center of the Earth," a 3-D movie inspired by the classic Jules Verne adventure tale.

"I've seen little boys jump into Daddy's lap, and then afterward fathers come up to you at the screening and say, 'Thank you so much for this movie,'" says Fraser. "Being a father myself, you'll take a hug from your son anytime you can get it."

"Journey to the Center of the Earth," opening in theaters today, is the first of two action extravaganzas starring Fraser this summer. "The Mummy: Tomb of the Dragon Emperor," which picks up a few years after the events of 2001's "The Mummy Returns," is due Aug. 1.

For Fraser, stopping in Atlanta with director Eric Brevig on a multi-city promotional tour, "Journey" is more than a movie.

"I think it's an overused term -- it's a roller-coaster ride of a movie," says the 39-year-old actor. "Well, this really has a roller-coaster ride in the movie, and I think it's safe to say ... probably the best roller-coaster ride that's ever been done in a movie ever."

"Journey" takes scientist Trevor (Fraser) and his nephew, Sean (Josh Hutcherson), to Iceland, where they and their guide, Hannah (Anita Briem), fall far beneath Earth's surface and face geological and zoological perils.

Fraser, veteran of big-time special-effects movies "The Mummy" and "The Mummy Returns," was hooked when he saw that the film was to be shot in 3-D. He describes himself as "a fan of stereoscopic imagery" and a "wannabe amateur camera enthusiast." He even has his own 3-D camera -- "and pocket protector."

But Fraser noticed some problems with the screenplay.

"Not knowing what the source material was -- because I, like Sean in the film, did not read that on my summer book-reading list -- I went and got the last copy at the Borders bookstore in Westwood," says Fraser. "And it was all right there in the book, how the structure should be."

Brevig, an award-winning visual-effects artist making his directing debut on "Journey," says he had hit a wall with the tale.

"It had become a father-and-son story, which sounds like a good idea until you actually look at what happens to the characters," says Brevig. "To give any sort of story arc to the relationship, you have to start off with the father not knowing the son very well.

"Brendan comes to me and he goes, 'It's the uncle in the book. It should be the uncle in the movie.' I'm like, 'Duh.'"

Working in 3-D was everything Fraser hoped. He enjoyed working against a blue screen.

"We had to use -- I guess there's not even a word for it -- the air-ball acting that comes with firmly believing that something's there when it is really not and then trusting that the CGI artists will put in whatever it is so that they believe it so that they can make the audience believe it," says Fraser. "So, basically, it comes down to just acting, or behaving in a way that gets you sent to the principal's office, but that's anther story."

Fraser plays down his expertise in acting against special effects.

"I've received a really good education, sort of like on-the-job training," he says. "With this film we're kind of breaking through a glass ceiling in giving the audience an experience that's been lacking."

Brevig believes this is a film for all ages.

"The movie is made for grown-up kids and not-yet-grown-up kids," he says. "The idea was to make something that young people will enjoy at one level and older people will really have fun because there's enough smart winks at the audience."

Fraser says his sons, ages 5 to 2, haven't seen the film yet and won't for a while.

"They're too small," he says. "They're all about SpongeBob [SquarePants] right now. They don't really understand movies. That's OK with me. I see SpongeBob as my Bugs Bunny."