The grumpy Goth teenager played with questionable credibility by Leelee Sobieski in "My First Mister" is, at first, an amusingly caustic cuss. We see the world through her contempt-filled eyes and take on her dark sense of humor as she complains in a matter-of-fact voice-over about life, the universe and everything.

Her name is Jennifer, but she prefers just "J." She's excessively pierced, quite premeditated in her anti-social disposition, and her mordant streak (she writes suicide notes on paper airplanes and throws them into public places) inspires weird social experiments. One day, just to see what will happen, she stomps into a suits-and-cardigans store for middle-aged squares and applies for a job -- decked out, mind you, in full rebel-girl regalia from her black lipstick to her Doc Marten's.

So imagine her surprise when the fuddy-duddy manager, played by the forever self-mocking Albert Brooks, hires her on a whim as the store's stock girl. A sardonic loner himself, Randall (she calls him "R") grows on "J" by countering her periodic verbal thrusts of sarcasm with droll, derisive parries -- and a friendship begins to form.

But while the talent of Sobieski and Brooks keep the characters appealing as they grow bizarrely but platonically fond of each other, actress-cum-director Christine Lahti lets the movie's raw charm of burgeoning mutual magnanimity slip away as their friendship turns into an implausible mentorship.

Randall helps Jennifer get her own apartment (on a stock girl's wages?). Jennifer begins to find her sunnier side and abandons the more radical elements of her lifestyle and wardrobe. Apparently happiness and facial piercings are mutually exclusive.

Before long the whole thing has taken on the air of a cautious, insincere TV movie -- a fantasy for 40-somethings about the warm heart they hope exists underneath the surly angst of today's scary teenage rebels. A real kid like "J" would laugh her butt off at "My First Mister's" syrupy second half and be insulted by Jennifer's transition into a very nearly vanilla girl who even begins bonding with her falsely chirpy housewife mom (Carol Kane).

Brooks and Sobieski emerge relatively unscathed from the deluge of sentimentality in the picture's second half because their banter is entertaining and because they're good enough actors to sell their peculiar relationship, even though is authenticity leaves a lot to be desired.

But when a movie starts out as trenchant as "Ghost World" then turns into something as mawkish as "Steel Magnolias," it's been botched, plain and simple.