Speaking from Among the Bones by Alan Bradley

In this book Flavia de Luce begins solving a mystery starting in the church: when they plan to exhume St. Tancred for the 500th anniversary of his death, little do the villagers of Bishop's Lacey expect to find a more fresh body in the tomb. But there is Mr. Collicutt, the organist who disappeared several weeks ago, and Flavia believes (as usual) that it's up to her to solve the mystery. In so doing, she finds that the roots of this mystery run deep--both beneath the church and into her own family history. The narrator of this audiobook was really excellent--in addition to the great story, it was a pleasure to listen to!