If your memory of Drew Barrymore is the 5-year-old girl whose older brother befriended "E.T. The Extra-Terrestrial," you may be in for a shock with the Drew Barrymore of "Poison Ivy."

Barrymore is the title character, a scheming 15-year-old nymphet (she was 17 when this movie was shot) who worms her way into a dysfunctional wealthy family and successfully turns it topsy-turvy. This is "Lolita" meets "The Bad Seed," with touches of everything from "Body Heat" to "The Hand That Rocks the Cradle" thrown in.

The film is told from the viewpoint of another 15-year-old, Sylvie Cooper (Sara Gilbert), who is friendless and introverted. She dresses in black, smokes cigarillos has an unenviable hairdo.

In the film's early scenes, Sylvie observes Ivy from afar, then meets her when they both get into trouble at school. It isn't long before Ivy and Sylvie, or "Cooper," as Ivy calls her, become best friends. And it isn't much later before Ivy moves in, taking over the attentions of Cooper's TV-executive father (Tom Skerritt), who is suffering from a midlife crisis and whose job is on shaky turf (he also drinks too much), and her bedridden mother (Cheryl Ladd), who is slowly dying of emphysema.

In short order Ivy is seducing Dad, wearing Mom's clothes and getting Cooper into even more trouble than usual.

But that's just the beginning of Ivy's malevolence, as Cooper gradually begins to realize.

Though on one level "Poison Ivy" is little more than salacious exploitation, on another it's almost a campy spoof of soap operas in general. In terms of plot devices, just about everything is thrown into this mix except the kitchen sink, and, dramatically, the film is so over the top it can hardly be taken seriously.

Yet, at the same time the film is so earnest, so deadly serious and so filled to the brim with artsy touches by co-screenwriter/direc-tor Katt Shea, that any humor — intentional or unintentional — is soon drowned out by the overall heavy-handedness.

The performances, however, are quite good. Obviously, Barrymore has the more flamboyant role and therefore is most noticeable, but Gilbert, who plays the tomboyish daughter on TV's "Roseanne," is awfully good in her role. Though Skerritt and especially Ladd's characters are really little more than plot devices themselves, the actors are good enough to keep from embarrassing themselves.

"Poison Ivy" is rated R for violence, sex, nudity, profanity and drugs.