Bones Never Lie by Kathy Reichs

Seventh Book in the Temperance Brennan series, Brennan is investigating a cold case that is related to a new case in Charlotte, North Carolina.  Andrew Ryan and Brennan originally investigated Anique  Pomerleau, a Canadian, wanted for abduction and murder of several young girls. Pomerleau disappeared and was never captured.
Even Brennan's mother, living in a mental health facility, with terminal cancer, does research that helps Brennan tie the two cases together.
Slidell, homicide, and Brennan, forensic anthropologist, often work cases together in Charlotte and now they are looking at a murdered young girl, Lizzie Nance. This time the case also involves the jurisdiction of Quebec and Brennan's old partner both privately and professionally - Andrew Ryan. Andrew Ryan has been on leave from his job since his daughter died. Brennan tracks Ryan to Costa Rica and persuades him that he is needed on the case. Pomerleau has resurfaced and may be responsible for the disappearance of Shelly Leal who may still be alive. Ryan is reluctant but as the case heats up Brennan and Ryan are once again working together.
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