Anthropological studies are by design once removed from their subjects - the observer observes, indicates patterns of behavior, draws conclusions, stands apart.

Robert Pulcini and Shari Springer Berman, the husband-and-wife writing/directing team behind The Nanny Diaries, consciously - and too cutely - take such a tack with their adaptation of the 2002 best seller. From the get-go, Nanny star Scarlett Johansson provides wry voice-over commentary as the camera pans a succession of museum dioramas: families through the ages from around the world, ending with that filial unit unique to present-day Manhattan. You know, the one with the preschool brat and the au pair - and the biological mother and dad tending to more important affairs.

Satire should be knife-sharp and whip-smart, and The Nanny Diaries never is. Johansson plays Annie Braddock, a middle-class Jersey girl just graduated from college without a clue as to who she is, or what she wants. After a Wall Street job interview gone awry, Annie has a putatively comic Central Park encounter with a kid named Grayer (Nicholas Reese Art) and the kid's out-of-sorts mom, Mrs. X (Laura Linney). Mrs. X is flummoxed because she's just lost her nanny, and has no idea what to do with the towheaded whippersnapper who sprang from her womb.

Thus, Annie - conversant in English, with a college degree - stumbles into a new career, hotly sought after by a swarm of wealthy Upper East Side women. Mrs. X wins out, and so begin Annie's adventures in wonderland: tending to an overbooked but underloved boy while his mother flits from charity function to Chanel fitting, and his father - Mr. X (an awkward, miscast Paul Giamatti) - fondles his coworker and takes lengthy business trips out of town.

Johansson, displaying flustered mannerisms that smack of one too many Woody Allen projects, goes about all this like the hopeful protagonist of a sitcom pilot. That is, attractive, amorphous, bland. Too embarrassed to tell her mother (Donna Murphy) what she's doing for a living, Annie confides only to her best friend, Lynette (Alicia Keys), and Lynette's gay roomie (Nathan Corddry). And then there's the so-called Harvard Hottie (Chris Evans), a preppy neighbor in the X's apartment building and an eager suitor - if only Annie would take him up on his offer of a drink.

Linney, who, on paper, seems tailor-made for the part of a cold, snooty New York socialite, never transcends the caricature penned for her by Pulcini and Berman. How the duo behind the terrific, Oscar-nominated American Splendor (which also starred Giamatti - to far greater effect) got lost in the foyers and fancy fooderies of the Upper East Side is anybody's guess. But lost they are, and so, too, is The Nanny Diaries.

There's a prop visible toward the end of this lackluster comedy: On the beach by the family's grand summer house, Mrs. X is seen reading a paperback: It's The Devil Wears Prada, another check-out-this-world chick-lit hit about a young outsider plunged into a cruel, alien subculture.

The filmmakers probably thought they were offering a clever little wink. But it's really a painful reminder of everything the film adaptation of The Devil Wears Prada is, and The Nanny Diaries is not.

The Nanny Diaries ** (out of four stars)

Directed by Robert Pulcini and Shari Springer Berman. With Scarlett Johansson, Laura Linney, Paul Giamatti, Chris Evans and Alicia Keys. Distributed by the Weinstein Co.

Running time: 1 hour, 45 mins.

Parent's guide: PG-13 (profanity, adult themes)

Playing at: area theaters