When Brennan has to recover the remains of a murdered elderly woman from a shallow grave in the midst of a freezing Quebec winter, she thinks she has the full set of 206 bones, but when she returns to her lab to analyze the remains, she discovers that certain crucial finger bones (that could confirm the identity of the victim) are not present.

Brennan soon discovers that an accusation of incompetence has been made against her: an anonymous phone call to the father of a murder victim alleges that Brennan neglected to observe trauma resulting from a bullet wound in the bones of an aging Chicago heiress that were found in the Quebec countryside some months previously.

The morale of the Montreal forensics team is poor, with the addition of a disruptive new recruit to the group, and the department head on extended sick leave.

Two more elderly women are dead or missing, and Ryan suspects that the force may be dealing with a serial killer.

In the process of solving the crime, Brennan also has to deal with an aggressive cat-hating neighbour and a cold case in Chicago involving a family link.