Nun Plussed: A Sister Mary Teresa Mystery

Writing as Quill, Ralph McInerney, author of the Father Dowling series, produces tales about Sister Mary Teresa (``Emtee'') Dempsey, a sleuthing septuagenarian nun. With the conclusion to this puzzler, however, the author commmits a major, if not mortal, sin, drawing his villain from outside the known cast. In her seventh appearance (after Sister Hood ), Emtee investigates the murder of a divorced former student who was stabbed to death in her Chicago home. The woman's ex-husband, an antiquarian book dealer who also restores rare manuscripts, confesses to the crime, although Emtee and her right-hand nun, Sister Kim, believe he is trying to protect someone else. Aided by another of Emtee's friends, a retired newswoman, they mount an investigation, to the dismay of Sister Kim's brother, a Chicago police detective. After another murder, the group--now abetted by the cop--sets a trap for the killer. Smooth prose and engaging characters only slightly mitigate the disappointment of the left-field solution. It's called culpable ignorance and McInerney, an accomplished pro, is guilty. (Sept.)