HIt should take nothing away from the achievements of new young writers of South Asian origin to state that Mukherjee eclipses all of them in her new novel, the highlight of her career to date. Only a writer with mature vision, a sense of history and a long-nurtured observation of the Indo-American community could have created this absorbing tale of two rapidly changing cultures and the flash points where they intersect. The narrator, 36-year-old Tara Chatterjee, was born into comfort and privilege in Calcutta. She and her two sisters are part of a close knit, snobbish Brahmin Bengali family, and the girls are raised to marry well. Tara, however, has brought shame to the family by divorcing her multimillionaire husband, Bish, and moving with their teenage son, Rabi, to Atherton, Calif., where the sudden intrusion of the past into her and her sisters' lives is only the first tremor of an earthquake that will undermine their safe assumptions. The narrative succeeds brilliantly in interweaving several themes of class, history and changing consciousness. Beneath the family drama and Tara's quest for her identity, Mukherjee tells a larger story about Indians in India and the U.S., painting a complex picture of vastly different cultures Hindu, Muslim, Parsi, Sikh further divided by substratas of caste and ancient prejudices, yet kept together by strict rules of family behavior and spiritual rituals. Finally, there's a very real current of danger running through the narrative that explodes into violence and irrevocable change. With remarkable dexterity, Mukherjee depicts tradition and myth colliding with the free will and dynamics of a one-world economy. Winner of the NBCC Award for The Middleman, Mukherjee has always been considered a significant writer. Here she bursts out as a star. 5-city author tour. (Mar. 31) Forecast: Mukherjee's perspective on the two societies she straddles is sharp and candid. Since she hasn't published a novel in several years, review attention and handselling should help this book find a discerning audience.