Time Out says
After the antics of his seven rambunctious children drive away 17 nannies, widower Mr. Brown (Firth) is informed by a mysterious voice that the right woman for the job is Nanny McPhee, a saintly hag whose snaggletooth and bulbous features would suggest a prime candidate for The Swan. The rest of the brood appears ready to succumb to McPhee's orders until the oldest son, an impudent rascal less willing to yield than Roger Toussaint, convinces them otherwise.
Based on Christianna Brand's kid-lit Nurse Matilda series, the film follows the un-Poppins-like nanny's attempts to tame the kids through her mystical brand of tough love (a rap of her cane pins the recalcitrant youngsters to their beds). Trouble arises when a batty aunt (scene-stealer Angela Lansbury) threatens to cut off the family's sizable monthly allowance unless Dad takes a new bride. Oblivious of this ultimatum—and, apparently, to the fact that it's impossible to feed eight mouths on an undertaker's salary—the little ne'er-do-wells attempt to sabotage their father's proposal to his sole marital prospect. As Nanny and her charges warm to each other, her monstrous warts miraculously vanish faster than you can say "Thank you, Dr. Zizmor," and the kids become much less given to pranks like pretending to have eaten the baby. NannyMcPhee isn't the most inventive children's fantasy film, but it manages to get its point across without ODing on didacticism or whimsy. (Opens Fri; see Index for venues.) —Erin Clements