Barrett's swank prose and her surprisingly sharp eye for emotional detail give an aura of freshness to this oldest of romance-fiction scenarios--the flashbacked career of a legendary Broadway star. She's Mary Gay, who, while preparing for her 75th birthday party in 1975 Manhattan, is robbed at gunpoint by a jewel-thief. . . which, of course, inspires Mary to remember her whole life. Born Mary Geylin, from a seriously musical Chicago family, young Mary vows never to sing (she feels guilty about her father's death), instead becoming accompanist to great vocal teacher Madame Selva. But handsome up-and-coming tenor Gianni (Johnny) Amara cajoles Mary into singing Mimi to his rehearsal Rodolfo--and also cajoles her into his bed--before he marches off to World War I. So gifted Mary begins studying voice, wows the locals with ""The Star-Spangled Banner,"" and is offered an operetta part on B'way from suave entrepreneur Charlie Grace. Opera or Broadway? Mary opts for the latter--partly because Gianni not only is reported missing-in-action but is revealed to have had a wife in Brooklyn! And soon Mary Gay is N.Y.'s favorite soprano, happy wife of successful Charlie, mother of son Lion and daughter April. Then, however, psychotically jealous Charlie dies in a boozy car accident (suicide?), and Gianni--not dead, though still married--re-enters Mary's life as her secret, sometime Paris lover. (She doesn't want to marry him; years later, he doesn't want to marry her.) Middle age also brings a much-younger lover in director Max, who is the Svengali behind Mary's 1950s comeback in a serious musical; unfortunately, he is (unbeknownst to Mary) the once-beloved of daughter April, who's doomed to unhappy marriage, a spotty showbiz career, and love-hate tensions with mother Mary. Finally, however, back in the present, son Lion sneaks in and wallops that robber, so Mary sails triumphantly off to her party--where everyone (including April) is ready to forgive, if not forget. Corny? Yes, indeed. But Barrett (Castle Ugly, An Accident of Love) paces the past/present montage nicely, avoids both gush and sleaze, and evokes musical theater with far more conviction than most romancers (the author's father is Irving Berlin). A classy, sometimes piquant diversion, then--especially for those with a fondness for the bygone lilt of light opera.