Sylvie Schiffer at 40 has a life most women dream about: a gorgeous home in the exclusive suburb of Shaker Heights, two perfect teenage children, a successful husband with a lucrative luxury car dealership. Sylvie has everything, it seems, but what she wants most: passion and romance -- moonlit cruises, holding hands, gazing at the stars. "When you're married," Sylvie sighs, "you don't even get kissed on the mouth." With building the business, raising the babies and creating their home, she and Bob hadn't found much time to focus on love. But now that the twins are off to college and the business is blooming, Sylvie is sure they will make their marriage bloom. So she believes until one day she does the laundry and notices those incriminating credit card receipts. Her husband has found romance, but it isn't with her. Bob is having an affair. Shocked and enraged, Sylvie fantasizes about a bullet to the leg (just to make Bob lame) -- followed by a hefty settlement. Her mother begs her to calm down: Her marriage is worth saving. Sylvie's having none of that. Out for blood, she sets off to confront Marla, the other woman. What she finds, however, is not what she expects. Looking at Marla is like gazing back in time: Except for 10 years and 15 pounds, Marla could be her twin. Marla has the best of Bob's love -- flowers, hot sex, breathy phone calls, candlelit dinner -- yet she admits to Sylvie that she lacks the thing she wants most: a husband and home of her own. "When you're single," Marla sighs, "you have to smell good 24 hours a day." Going beyond revenge, Sylvie hatches a brilliant scheme to make them both winners and bring Bob to his knees. But will they end up with what they want or walk away empty-handed and broken-hearted? No one defines modern love, work and sexual warfare better than New York Times   bestselling author Olivia Goldsmith. In her most surprisingly ingenious novel yet, she once again speaks as the voice for her gender when she points out a truth not universally acknowledged until now: All wives yearn for the romance of being a mistress and all mistresses yearn for the security of being a wife. The First Wives Club (1992) proved how well Goldsmith could get into the psyche of the scorned wife. Here, she makes even the mistress a sympathetic character. Sylvie has the makings of a perfect life--marriage to a successful, loving man; well-adjusted children; beautiful house in the suburbs. But just when she's ready to reclaim the romance in her marriage now that her kids are in college, she realizes that Bob has a girlfriend on the side--Marla, a younger version of Sylvie. When she's finally ready to confont Bob, she is inspired to confront Marla instead, and, after meeting the ditzy blond, she discovers that each of them is seeking what the other has: Sylvie longs for romance and spontaneity, Marla for a stable family life. Sylvie convinces Marla to swap identities for two weeks to see what it's like in the other's shoes. After a retreat to alter their appearances, the charade begins. Goldsmith has a knack for telling a funny story, and she is at her best here. If readers can get beyond the operalike disguise premise, they are in for a buoyant ride through a crazy tale of love and family, betrayal and revenge. A movie version is already in the works. Stock up. Mary Frances Wilkens More monumental high-concept from Goldsmith (Marrying Mom, 1996, etc.), this time in a wonderfully funny fable about a wife and mistress who reverse rolesand a husband who apparently can't tell the difference. Sylvie Schiffer lives in happy domestic comfort with perfect husband Bob in a well-ordered colonial home in the plush Ohio suburb of Shaker Heights. There, Sylvie is surrounded by her perfect family (including her outspoken mother Mildred, who owns a ceramic store called Potz Bayou); she brews perfect cups of aromatic tea; she plays a perfect Steinway piano with an ebony lacquer finish; and in winter a fireplace fills her music room with the comforting scent of applewood. But not all is well in Sylvie's middle-class paradise. She's turning 40, her children are in college, and she wouldn't mind some marital passion to take up residence in her empty nest. But Bob, whose greatest passion seems to be his BMW ``Beautiful Baby,'' hasn't made love to her in months; instead, he's found a delicious little number by the name of Marla (does Donald Trump live in vain?), who works as a reflexologist (with a little toe-sucking on the side) and who incidentally looks a lot like a younger version of Sylvie. When Sylvie discovers the resemblance, she hatches a plot to ``switcheroo'' with Marlashe'll find out what it's like to be loved by her husband again, and Marla can experience the joys of having a man of her very own and a kitchen with an island in the middle. In another of Goldsmith's trademark transformations, Sylvie gets a face-life and tones up, while Marla eats banana-cream pies to fill out. It all culminates with