With that Disneyland metaphor, director Kirk Wise convinced studio chief Michael Eisner to give the green light to “Atlantis: The Lost Empire,” a Jules Verne-style adventure about a group of explorers searching for the fabled continent. Unlike most Disney films, “Atlantis” is a non-musical feature, with rousing action scenes and a more complex plot than the studio is known for.

“The grandparents of this movie are really ‘20,000 Leagues Under the Sea,’ ‘Journey to the Center of the Earth’ (and) there’s a little bit of Edgar Rice Burroughs and H.G. Wells thrown into the mix,” Wise says. “(There’s) just very much that rich tradition of romantic adventure.”

On a recent promotional visit to Kansas City, Wise, along with producer Don Hahn and animator John Pomeroy, spoke of their desire to try something different, while still maintaining the qualities that have made Disney animation so successful over the years.

“We didn’t want to make this action movie that was just about explosions and a thrill ride and something that had no humanity to it,” Hahn says. “We wanted to bring something to bear on the action genre that we felt like we did well, and that was emotion and investment in a human story.”

Despite the Disney label, “Atlantis” is rated PG and seems to be for slightly older viewers. “We didn’t consciously set out to aim the movie toward a particular segment of the audience,” Wise says, and Hahn agrees, adding that the team can’t afford to worry too much about how a segment of the fan base may or may not react.

“You’d be so terrified to make a move that you would never be able to make a decision,” he says. “You’d just be frozen.”

He also jokes that their movies aren’t rated G or PG, they’re rated “Disney,” and that brings with it a certain amount of pressure. “There’s tremendous goodwill and tradition and history” associated with the Disney name, Hahn says. “And there’s also tremendous baggage and political pressures and a very scrutinizing audience.”

Living up to those people’s expectations is a huge undertaking, and anyone working on a Disney feature should expect to make a lengthy commitment. “It’s like a marriage,” says Hahn of the 4 1/2-year job. “You want to make sure you can sign up to this and survive it and reach the end of it.”

Building ‘Atlantis’

The early stages of production on “Atlantis” involved hashing out the structure of the story, then moving on to storyboarding, drawing basic panels to represent each shot. “When we start working on the storyboard form, the whole thing becomes very fluid,” Wise says. “Once those sketches go up on the wall, that becomes the working tool. That’s where you make your revisions and your discoveries and your tweaks and your changes.”

The whole process was highly collaborative, with several people throwing out script and dialogue suggestions, and revisions being made continually, under the supervision of Hahn, Wise and co-director Gary Trousdale (who also collaborated on “Beauty and the Beast” and “The Hunchback of Notre Dame”).

A little over a year into the project, Pomeroy was brought in as the supervising animator for the character of Milo Thatch, the leader of the Atlantis expedition, voiced by Michael J. Fox. Pomeroy began work in November of 1997 and immediately found himself having to change his style to match that of comic book artist Mike Mignola (“Hellboy”), whose work directly inspired the look of the film.

“It took me about six months to understand and adapt my drawing sensibilities,” Pomeroy says. “(But) once I did, I’ve enjoyed it so much that it’s hard for me to get out of that style.”

Pomeroy found it much easier to understand the character he was helping create. “There was something immediate to me about Milo,” Pomeroy says of the film’s hero, who is ridiculed for his theories about the Atlantean civilization. “He’s got wonderful hopes and aspirations, but nobody will give him a chance. We’ve all been in that position once in our lives.”

Pomeroy’s identification with the character was such that his wife even started calling him “Milo” around the house. “It’s the closest thing I’ve come to animating what I would call a self-portrait,” he says.

The character’s appearance came from various sources. While Fox was the most obvious template, Pomeroy and his team looked to everyone from Cary Grant to Charlie Chaplin for inspiration. One of their toughest challenges was providing the right level of dramatic subtlety for the film’s more serious style.

“Usually, when you’re thinking of animation characters and acting, you think of facial mugging,” he says. “You don’t think OK, take this character and animate him with a broken heart’ or ‘Take this character and make him look depressed.'”

Use your illusion

Pomeroy found this aspect of his job particularly exciting, if difficult, since he believes viewers are more concerned with the realism of human characters.

“You’ll be more forgiving if you see a horse that isn’t moving quite right, or a dog, or a cat,” he points out, but with humans, “it has to be 100 percent right on, or else the illusion that we’re carefully trying to build just unravels.”

That illusion is key to pleasing Disney’s legions of fans, although Hahn acknowledges that this isn’t easy.

“It’s impossible, obviously, to please our whole audience,” he says. “But I think it’s possible, on some level, to entertain our whole audience.”

As they make that turn into Adventureland, the creators of “Atlantis” can only hope viewers are ready to buckle up and enjoy the ride.