After two modestly entertaining novels with flickers of contemporary seriousness (Compromising Positions, Close Relations), Isaacs goes all out for soap, sex, and sentiment in this three-generation saga of happy/unhappy marriages: a Danielle-Steel-style wallow except for the X-rated antics and a certain urban, ironic sharpness. Jane Cobleigh, TV celebrity and estranged wife of Nick Cobleigh, ""the world's most famous actor,"" lies near death in a coma--after being hit by a car. (She was on her way--sigh--to a reconciliation with superstar Nick in London.) So, while we wait to see if Jane will survive, Isaacs flashes back to narrate the marital ups and downs of the Cobleighs and their recent ancestors. Jane's grandmother is Rivka Taubman, a Lower East Side teenager who gives unwed birth at 15 to baby Sarah; Sarah grows up zaftig, changes her name to ""Sally Tompkins,"" wears herself out in vaudeville and burlesque, then manages to snare naive, handsome accountant Richard Heissenhuber of Cincinnati, who's overcome by lust. . . and sires Jane. But the marriage is rocky (vulgar Sally, prim Richard), Sally dies in a freak accident, and poor Jane is raised by hateful stepmother Dorothy--who dotes on her own spectacularly handsome son Rhodes (while Richard, a frustrated milquetoast, is both abusive and incest-y with Jane). Meanwhile, far from middle-class Cincy, handsome young lawyer James Cobleigh--son of a shyster-father and an alcoholic/blueblooded mother--is sweeping homely, red-haired heiress Winifred Turtle off her horsy feet. But, again, the marriage is only blissful for a while: Win is too rich, too dull, uninterested in politics; James, with the OSS during WW II, falls for a brainy Frenchwoman; a postwar reconciliation is creaky, with James (trapped in a Wall St. job) philandering and Win institutionalized for depression. So their oldest son, handsome Nicky (all the men here are handsome in the extreme) will opt for a more bohemian life. At Brown he dabbles in acting, meeting Pembroke actress Jane (dark, exotic), his cultural mentor; passion blooms--with early marriage and summer-stock/cold-water-flat days. Nick stars on Broadway, then in movies--while Jane, who gives up her own career for Nick and children, succumbs to a galloping case of agoraphobia, not leaving the house for six years. And eventually noble Nick will slide into kinky adulteries--though the marriage doesn't collapse until Jane gets a cure, a lover (her first orgasm!), and an independent career on TV talk-shows. Will most readers care whether Nick and Jane get back together, whether Jane emerges from her coma? Perhaps not--since neither character is fully convincing or appealing. Half-baked, too, is an extraneous subplot involving Jane's homosexual brother Rhodes. But the earlier generations have color and bounce; there's a generous assortment of backgrounds (high-society, show-biz) and ailments; so, with Isaacs' prose delivering a bit more sass than customary in such pre-fab assemblages, there should be a sizable audience for this formula-smorgasbord of courtships and childbirths, lusting and bickering, glamour and misery.