Your enjoyment of "Extremely Loud and Incredibly Close" depends on whether you prefer sincerity to authenticity.

The protagonist, Oskar Schell, is a 9-year-old waif with Asperger's whose father died in the World Trade Center. The story (from Jonathan Safran Foer's 2005 bestseller) follows Oskar's therapeutic voyage across New York City, where kindly strangers help him connect a key left by his father with its mysterious lock. The film charts a path of growth through tragedy, as Oskar discovers the world in all its many-splendored glory and ends in a glow of uplift.

Did your heart wrench a bit in your chest? Did you feel a tidal surge of luxurious sentimental warmth? Good for you. Innocent Oskar and his isn't-life-wondrous adventures left me disappointed, depressed and somewhat irritated. The obliteration of thousands of lives on 9/11, the death of Oskar's father, they're just grist for the story. Oskar finds his redeeming triumph over trauma, and that's all that really matters. It feels like too big a price for the payoff.

The film is directed in magic-realist fashion by Stephen Daldry ("The Hours"). With soft focus, impressionistic aerial views and a romantic, Maxfield Parrish color palette, he imbues a gritty city with fairy-tale coziness. It's not in the execution that the film fails but the concept.

The fall of the Twin Towers is irrefutable evidence that the world is a harsh, dangerous place, yet the worst people Oskar encounters are sheep in wolves' clothing. Here and there is a gruff citizen, but no one is wild-eyed or unscrupulous. Really? What may have worked on the pages of a novel collapses before our eyes onscreen.

Young Thomas Horn is a fine actor, especially when his character is in a sour mood, but one gets very tired of Oskar's relentless precocity. As the boy's elderly sidekick, a gimmicky, nonspeaking role that could have been a sentimental deathtrap, Max von Sydow emerges mostly unscathed. The same can't be said for the audience. "Extremely Loud" does everything to compel our tears but feed us into a wringer.

It's not sufficiently sad that Oskar's dad dies. He must die in a national catastrophe. And the dad is Tom Hanks at his cuddliest. And his widow is Sandra Bullock in full-on heartbreak mode. The casting overkill extends to the very doorman in Oskar's apartment building, the formidable John Goodman in a throwaway role with perhaps a dozen lines of dialogue. With such prominent actors in even walk-on parts, the filmmakers would have us believe, surely this must be a weighty, important work of art. Taking a cue from its over-amped title, the film virtually shakes us by the shoulders to drive home its significance.

At one point in the film, Oskar's father plays a lively game of dueling oxymorons with his son to thaw the boy's communication anxiety. Dad says "deafening silence" and the boy retorts "living dead." The word game inspired an oxymoron describing this movie: "ponderous wisp."