Flavia stumbles across a mystery in her church, St. Tancred's. While they're planning to unearth the old saint's body, a recent body is found in the crypt. Flavia has a little competition in her sleuthing in the form of a private investigator who says he's there to unearth medieval seeds from the saint's burial. 
 A convoluted plot, but Flavia figures it all out in the end . . . where Bradley drops a giant twist. 
 Maybe not my favorite of the Flavia de Luce series, but it holds up.