This time out, Boston's tough/sentimental p.i. John Cuddy (Yesterday's News, etc.) is asked by an old friend to find out who's sending nasty, threatening notes to law professor Maisie Andrus. Andrus--a right-to-die advocate whose recent book has made her a public figure (plus a raft of enemies)--is now married to ex- tennis pro Tucker Hebert. Dr. Enrique Duran, her first husband, died in Spain, with her help, after a paralyzing stroke. His deaf- mute servant and protÇgÇ Manolo is still with Andrus, guarding her, as does solicitous secretary Ines Roja, a Cuban refugee. Cuddy talks to everyone even remotely involved with Andrus--stepson Ramon Cuervo; enemy academic Walter Strock; gay activist Alec Bacall; pathetic Louis Doleman, whose daughter committed suicide after reading Andrus's book, and even Gunther Yary, head of a neo-Nazi hate group. But nothing can save Andrus--and only the vivid characters, lots of Marathon lore, and the Boston backdrop salvage the far- fetched plot in this flawed but lively entertainment.