Nanny McPhee

Like a demented, songless mixture of "Mary Poppins" and "The Sound of Music," Kirk Jones' "Nanny McPhee" stars Emma Thompson as an eccentric nanny with an agenda. Her specialty is convincing Mr. Brown, the recently widowed father of seven brats, that she can whip the kids into shape.

Looking more like an alcoholic witch than a child tamer, Nanny McPhee has a bulbous W.C. Fields nose and one very long upper tooth that embraces her lower lip. Her warts are plentiful and hairy, though they disappear gradually as she works her way into the family's routines.

The most resourceful and obnoxious of the children, Simon (Thomas Sangster), prides himself on the fact that he and his insubordinate siblings have sent 17 nannies packing. Addicted to playing with his toy guillotine, familiar with fairy tales and their abundance of wicked stepmothers, he's also fearful that Dad (Colin Firth) will rush into a disastrous marriage.

This lends a touch of method to the kids' madness, though it's ultimately self-defeating. They don't realize how much their father owes to their monstrous, half-blind aunt, Adelaide (Angela Lansbury), who announces her intention to break up the family by taking one of the kids away.

Based on Christianna Brand's series of "Nurse Matilda" books, the movie was written by Thompson, who sometimes seems at odds with director Jones (who made the clumsy art-house hit, "Waking Ned Devine"). Her script holds together better than his lamentable attempts to mix slapstick and schmaltz; the picture sometimes appears to be at war with itself.

Nevertheless, it's so well-cast — and the décor and special effects are so delightfully garish — that you may find yourself cheering the clever bits that do get past Jones' fussiness. The picture almost succeeds in creating its own unique fantasy universe, where spoiled children can feel justified in tying up their cook (Imelda Staunton) and trashing her kitchen.

When they make a royal mess of the place, the magical McPhee is there to straighten things out, restore the damaged bits and put them back in their places. She brings the same kind of order, of course, to Dad's love life, which includes a no-contest contest between a predatory harpy (Celia Imrie) and a sweet-natured maid (Kelly Macdonald).

McPhee is a master of reverse psychology. When the children claim that they've come down with the measles and can't get out of bed, she takes note of the spots painted on their faces, then announces that not only can't they get out of bed, they're imprisoned there. Mass hypnosis or magic? It's never quite clear, though she accomplishes exactly what she intended — with the help of a writhing, repulsive tablespoon of measles medicine.

Hidden behind pounds of makeup, Thompson occasionally struggles to express her character's reactions. Still, this limitation does help to emphasize the character's enigmatic qualities. She's forever making pronouncements about the difference between "need" and "want," making sudden and unwanted appearances and then claiming "I DID knock," while maintaining a sense of mystery and self-assurance that can't help but bedazzle.

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