This was a great end to the Mercy Series. I really enjoyed the book.
The Mercy Street Foundation was set up in the first book of the series, Mercy Street. It was founded by the billionaire, Robert Magellan, his cousin Father Kevin Burch and former detective Mallory Russo. The goal of the foundation is to look into cold cases that the various police departments have run out of leads on. They do this at no cost to anyone.
The foundation is still in the process of staffing all the positions. When the application of a former FBI profiler comes across Mallory's desk, she jumps on the opportunity to interview him.
Sam DelVecchio, left the FBI after the death of his wife at the hands of a serial killer he was tracking. He has just come back from a long vacation trying to clear his head, and decide what he wants to do next. When he finds the information on the Mercy Street Foundation. He needs a job, and figures it cant be any worse than what he left behind.
Sam's first case is the murder of a husband and father, an all around good guy that was found behind the center he and his wife volunteered at feeding the homeless. All leads have been followed, and the case has gone cold. The detective working the case mentions that an agent with the FBI has looked into the case in connection with one she is working on.
Fiona Summers has worked with the FBI for over 12 years, she has a tough reputation, no nonsense, and everything strictly by the book. When she is contacted by Sam about his case, they get together and compare notes and discover that not only do they have a serial killer on their hands, their killer is choosing dates and places that have a connection to Sam. It's only when Father Kevin sees the photos that he suggests, by the way the victims have been left, the killer is reenacting the seven Acts of Mercy. Three down four to go and Sam is sure he is to be number seven.
In a side story, Robert has been searching for his wife and infant son since the first book, they've been missing for fifteen months. Part of that story was resolved in the last book, Cry Mercy. We get the conclusion to the story in this one.
This series so far only has the three "Mercy" books. But it is part of her FBI series. It can be read as a stand alone book. I've read them all, and find she likes to bring back earlier characters or sometimes just a quick mention of a person or a case. It's like getting a visit from an old friend when they pop up in another book.
I hope this is not the last book in the series.