Tempe Brennan, the forensic anthropologist who stars in Kathy Reichs' best-selling mystery series, is a good woman who does grisly work. In Grave Secrets (Simon &and Schuster Audio, $26, 5 hours, ISBN 0743525019), her latest and most affecting book yet, Tempe is in the Guatemalan highlands helping human rights workers identify the bones of women and children who were massacred by the army during their long, horrific Civil War. When a body that may be linked to the disappearances of several young women is found in a septic tank (one of Tempe's least favorite specialities) in Guatemala City, Tempe is asked to join the investigating team. It's a tricky identification that leads to a trickier state of affairs one that could implicate the Canadian ambassador and his determinedly difficult daughter. Doing her professional best to work with both the past and present murders, Tempe begins to realize there might be a slender connecting thread, but it's a thread that just might choke her. As she has done before, reader Katherine Borowitz meets the challenges of many accents and many voices with absolute aplomb.