The Order of the Sisters of Divine Grace is  holding a convention on the Philadelphia campus of St.  Elizabeth's College--and the list of invitees is  studded with unlikely Main Line luminaries like  charmless coronation king Henry Hare and fat,  foul-mouthed Norm Kevic, the most-talked-about radio talk  show host in Philly. Also on hand is guest speaker  and retired FBI agent Gregor Demarkian. The  festivities include a reception and buffet dinner. .  .which turns into a Last Supper for the nun who keels  over due to a fatal case of pate poisoning. It's  murder for mother's day--Who stuffed the ice  sculpture with fugu, a foul-smelling, potentially lethal  Japanese food fish? And why kill a nice nun like  Sister Joan Esther when it's the truly evil Mother  Mary Bellarmine whom everyone despised? Demarkian  has to sort through an ever-shifting maze of facts  and suspects--including a Society Hill matron who's  no saint and a minor celebrity with a very bad  habit-before he can crack a case in dire need of  divine deliverance. . .from death.

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