Depicting mental illness on screen is such a difficult undertaking, both for its inherently internal nature and because of the obvious need for sensitivity. When we're talking about a child who's suffering psychologically, the prospect becomes even trickier.

Writer-director Daniel Barnz manages to achieve a true and delicate balance for much of "Phoebe in Wonderland," his first feature, but ultimately undermines himself with heavy-handed and rather hackneyed whimsy.

Elle Fanning, like older sister Dakota, shows preternatural poise and wisdom beyond her years, as she did last year playing young Daisy in "The Curious Case of Benjamin Button." Here, she stars as Phoebe, an imaginative 10-year-old whose playfulness devolves into unruly and self-destructive behavior.

She finds a sanctuary from her demons and impulses when she lands the lead role in her school's production of "Alice in Wonderland." She's a natural, and she receives encouragement from drama coach Miss Dodger (Patricia Clarkson), who recognizes in Phoebe a kindred misfit spirit. (Phoebe also finds a lone friend in fellow outcast Jamie, a little boy who brings his own costume to audition for the role of the Red Queen; Ian Colletti plays him with amusing flamboyance.)

But she continues acting out in class and on the playground, repeatedly getting called in to see the principal (Campbell Scott) for spitting at other students. At home, she tortures and ultimately injures herself with obsessive-compulsive behavior, like washing her hands too often and going up and down stairs in a peculiar pattern.

Her mom, Hillary (a no-nonsense Felicity Huffman), doesn't want to accept the diagnosis she receives from Phoebe's psychologist. She thinks, and understandably so, that kids will be kids and they'll go through phases, and that's how she justifies her daughter's rash acts. Instead, she tries to ground Phoebe with love and stability. (She also happens to be a writer working on a book about "Alice in Wonderland," which is a bit too convenient.)

The scenes in which Phoebe interacts with her mother, father (Bill Pullman) and precocious younger sister (Bailee Madison) are the strongest, though; they're rooted in reality as the family struggles with the eldest child's daily ups and downs. Clarkson, too, brings her usual understatement to a daffy character who spouts facile platitudes about risk-taking (as well as lines from Lewis Carroll's "Jabberwocky").

But increasingly, Phoebe sees "Wonderland" characters wherever she goes: her mom as the Red Queen, for example, or her psychologist as Humpty Dumpty. The conceit, with its vibrant colors, bright lighting and amped-up energy, quickly grows cloying. And Barnz didn't need all that in trying to portray what's going on inside Phoebe's mind: The realism is more powerful, and Fanning is mature enough as a young actress to pull it off.

Ultimately, "Phoebe in Wonderland" feels like a well-intentioned, made-for-Lifetime movie _ not surprisingly, the Lifetime Network is among the film's distributors _ albeit one with an artsier visual aesthetic.

"Phoebe in Wonderland," a ThinkFilm release, is rated PG-13 for thematic material and brief strong language. Running time: 96 minutes. Two and a half stars out of four.

Motion Picture Association of America rating definitions:

G _ General audiences. All ages admitted.

PG _ Parental guidance suggested. Some material may not be suitable for children.

PG-13 _ Special parental guidance strongly suggested for children under 13. Some material may be inappropriate for young children.

R _ Restricted. Under 17 requires accompanying parent or adult guardian.

NC-17 _ No one under 17 admitted.

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