Sis Boom Bah

With the snappy style her readers have come to expect, Heller (Princess Charming; Crystal Clear) presents another breezy tale of modern women; this one explores the bitterly antagonistic relationship between two sisters, and the murder mystery they become embroiled in. Deborah Peltz, 43, a soap-opera writer living in New York, gets fed up with big city life and moves to Stuart, Fla., where her mother lives. Unfortunately for Deborah, older sister Sharon, a fortune-hunting, desperate three-time divorc e, also lives there. Sharon has always resented Deborah, both for being born and for making the high school cheerleading squad. Their feud is petty and regenerative, and neither sister is willing to let it go, but when the two women aim to seduce the same man only to find him murdered, a new alliance must be forged. The situation turns Deborah into an amateur sleuth and puts Sharon in the hands of a murderer, but the mystery here is not particularly complex or suspenseful. Heller focuses instead on the bickering between the sisters, continuously driving home the maxim that ""having a sister means always having to say you're sorry."" Heller's female characters suffer a particularly harsh comic treatment, most of them obsessed with money, men, shoes or social position. One only hopes that Heller's humor is tongue-in-cheek when the supposedly worldly Deborah is forced to say things like ""the Big Apple had its share of Bad Apples."" Heller writes briskly and cheerfully, and readers looking for light fiction with a decidedly contemporary theme probably won't be disappointed at the simplicity of her unfettered characters and implausible plot. Agent, Ellen Levine. (May)