In "Lady in the Water," Bob Balaban does a riff on originality that brings the house down -- when the house is packed with critics.

Paul Giamatti is Cleveland Heep and Bryce Dallas Howard portrays Story in "Lady in the Water." Click photo for larger image. 'Lady in the Water' Rating: PG-13 for some frightening sequences. Starring: Paul Giamatti, Bryce Dallas Howard. Director: M. Night Shyamalan. Web site: ladyinthewater.warnerbros.com/ Family Film Guide A real storyteller: Imaginative Shyamalan takes leap of faith 'Lady In The Water' stars had some slippery challenges

Balaban plays a film and book critic who has just moved into The Cove apartment complex managed by Cleveland Heep (Paul Giamatti). The sourpuss writer declares, "There is no originality left in the world, Mr. Heep."

Is that filmmaker M. Night Shyamalan pre-empting his critics? Or taking a playful jab at reviewers who have hailed him, hated him and fallen somewhere in between, all within a half-dozen years?

Say what you will about "The Sixth Sense," "Unbreakable," "Signs" and "The Village," Shyamalan is nothing if not original. "Lady in the Water," a fantasy about a narf, or sea nymph, living beneath the apartment complex pool, is unlike anything else at the multiplex.

Giamatti plays a broken-spirited man trying to help the narf named Story (Bryce Dallas Howard), who ends up seeking shelter in his bungalow. Instead, Heep may be saved by Story and a story, by a renewed sense of faith and community, by a childlike ability to believe there is another world lurking outside, below the water, deep in the grass, beyond the clouds.

"Lady in the Water," written and directed by Shyamalan, is set at an apartment complex occupied by an oddball assortment of tenants.

As in "Rear Window," no two are alike: a college student and party girl (Cindy Cheung) and her strict Korean mother; a stalled writer (Shyamalan) and his roommate sister (Sarita Choudhury); a crossword puzzler (Jeffrey Wright) and his young son; a man (Freddy Rodriguez) who exercises only the right half of his body; young slackers who flout the rules about smoking; and others.

As Heep tries to help Story return to "The Blue World," he finds himself navigating a world filled with mysterious words -- narf, scrunt, kii, tartutic, the Great Eatlon -- and rules. Lots and lots of rules.

Heep, a man who has plenty of reasons to feel sad and dispirited, must become almost childlike in his ability to listen to a story that will show him the way.

In one playful scene, he happily munches cookies, sprouts a milk mustache and settles in, as an elder enlightens him. In another, an adult with her hair in ponytails tries to extract information while playing an elaborate game, with its roots in adolescence.

Heep draws his neighbors into his quest, which turns out to be about more than he first imagined.

The movie is based on a bedtime tale Shyamalan invented for his young daughters. Shot in a way to simulate twilight, it was filmed 20 miles outside of Philadelphia at a pool and apartment building created for the production.

Howard, whose breakout performance in "The Village" was remarkable, looks almost ethereal here. Her skin is nearly translucent and she speaks and moves in a manner that conveys she's not of this world.

Giamatti, as usual, is the ace in the hole. The Oscar nominee ("Cinderella Man") has to slump from pain and buried guilt, scramble around the Cove carrying Howard and sob, none of which is easy.

They are part of an excellent, unusual ensemble, with Cheung and Choudhury proving to be scene stealers and veterans such as Mary Beth Hurt, Bill Irwin and Jared Harris among the players in small roles.

The cast, however, is almost too big, and you imagine actors elbowing each other for camera time. "Lady" buckles under the weight of information overload, from elaborate details about the narf's friends and beastly foes (the scrunt, with its poisonous scratches) to TV war reports humming in the background and portents of things to come.

Shyamalan "swings away," to borrow a phrase from "Signs." The world he's spun is imaginative, putting Balaban's contention to shame, but way too complicated and arcane for my earthbound tastes. Too often, you're left feeling like Heep, when he's swimming through underwater passageways without an air tank.