Gia.

One of the scattered pleasures of HBO's new movie Gia is the revelation that top fashion models keep personal journals, and if that fact strikes you as odd, just ask yourself this: If you were required to spend hours waiting for a shot to be set up, surrounded by flighty hairdressers and stylists, what would you do to maintain your composure? Easy -- take drugs or buy a notebook.

Gia Carangi, top model and the main character here, scribbled regularly in her notebooks, and if her story -- difficult Philadelphia childhood, rapid rise and precipitous fall in the fashion business of the late '70s and early '80s, death from AIDS complications -- is too filled with schoolgirlish stabs at poetry to be very interesting, it at least provides a competent framework for this quite watchable two-hour movie.

Most of the picture's best moments come in the first half. We watch Gia, played with conviction by Angelina Jolie, bump up against the haughty superficialities of Manhattan's fashion scene, as embodied by maternally bitchy models maven Wilhelmina Cooper (Faye Dunaway, a little less scary than usual). By temperament Gia is ill-suited to scale these heights; street-tough and love-starved, she brings to mind the remark of the butler -- played by John Gielgud -- to the distinctly downscale Liza Minnelli in Arthur: "One generally meets women of your sort in bowling alleys. "

Gia, however, turns her uninhibited vulgarity to advantage. Early in the movie, for example, during a photo shoot she uses her boyfriend, T.J. (a touching Eric Michael Cole), to divert a photographer's interest. She sits back and enjoys the men's make-out session, and for an all-too-brief moment, it seems as if the movie win focus on her Joe Orton-like delight in devilry. Even her on-and-off affair with a stylist named Linda (Elizabeth Mitchell) has some initial bite, not to mention steamy coupling.

But before long drugs take over Gia's life, and the element of surprise disappears from the movie. To be fair, there are some effectively rendered scenes of this addiction: Gia disturbingly blank-faced as she takes her first snort of heroin in the backseat of a limo; Gia's mother (realistically played by Mercedes Ruehl, though with an inexplicable Marge-from-Fargo accent) torn in ten directions when she tells her strung-out daughter that she cannot move back home; Gia trying to score smack on the street and being bounced around like a pinball between sadistic dealers.

If the movie's last chapter, with Gia in and out of rehab before dying, does not deliver much emotional wallop, it is not the fault of director Michael Cristofer or screenwriter Jay McInerney (who cowrote with Cristofer). A struggle with drugs is almost impossible to bring to life in ways that compel our interest rather than our sympathy, and when you are dramatizing the life of someone like Gia Carangi -- who seems more a totem of pre-AIDS excess than a character sufficiently complex for a full-length feature -- such a challenge can defeat even the greatest of filmakers.