Never before has Louis Auchincloss emerged so clearly as the stepchild of those literary honeymooners, Henry James and Edna Ferber. Perhaps that's bemuse he has rarely strayed so far from his home base inside male Anglo-Saxon classrooms and boardrooms; here the financial-social combatants are Jews--the late-1930s New York clan of Judge Irving Stein--and women: Stein's society wife Clara, fashion-mag editor Ivy Trask, and Ivy's protÃ¨gÃ¨e Elesina Dart, a well-bred, on-the-skids actress ogled by all as an ""odalisque."" Judge Stein is second-generation rich, assimilated (""Some of my best friends are anti-Semites""), but he's never been sanguine about ice-matron Clara's blueish blood, not even with his townhouse, his Rye estate, and his museum-rivaling art collection. SO he's an easy target for Machiavellian, frustrated Ivy (""I'm neuter!""), who Pygmalions Elesina into Stein's dining room, heart, and bedroom. A quickie divorce, and Elesina is mistress of the Stein empire, and--when Stein is wheel-chaired by soon-fatal heart attacks--of David Stein, the only son to have inherited his father's romantic and intellectual sensibilities. So far, so Jamesian, sort of, but what follows--David's WW II death, Elesina's postwar political rise (she brilliantly wards off McCarthyish smears), Ivy's head-over-heels suicide jump when Elesina replaces her with a trendy, gay aide-de-camp--is a whole other, lesser set of clichÃ¨s. And the page-by-page Auchincloss graces fade with the years, from the just-rightness of Clara's ""People are a cul-de-sac"" to dialogue that suggests either mishandled satire or sheer laziness: ""Let us not cross Rubicons and burn bridges"" . . . She: ""It's a game; it's not the rubber""/He: ""And you want a grand slam!"" Perhaps Auchincloss never decided whether these people were worthy of real writing, and all the fine dinner talk--art, opera, and Shakespeare--can't disguise the wind-up moves, the wobbling tone, and the lowered sights on an assured audience.