Another book in the Donaghue and Stainer series by Michael J. McCann, The Fregoli Delusion provides another good mystery along with information about a rare condition:
The Fregoli delusion, or the delusion of doubles, is a rare disorder in which a person holds a delusional belief that different people are in fact a single person who changes appearance or is in disguise. The syndrome may be related to a brain lesion and is often of a paranoid nature, with the delusional person believing themselves persecuted by the person they believe is in disguise. (Wikipedia)
Never having heard of this disorder, I found a mystery centered on a character's strange disability compelling. Having a witness to a crime, but one that is subject to compulsive misidentification, presents a unique problem for Donaghue and Stainer.
The reason I liked Blood Passage so much was because of the way the crime revolved around the idea of children and past lives, and McCann's research into the studies concerning this phenomenon. The twist that The Fregoli Delusion presents makes this murder investigation much more interesting. It isn't that difficult to figure out (at least for the reader), but proving it is a conundrum.
Once again, although part of a series, each book works perfectly as a stand-alone.
Mystery/Police Procedural. 2012. 268 pages.