Normally, I remain skeptical when the killer targets a policeman, or the cop's personal history or family intervene into the plot. In this case, however, Bolton pulls it off. The events in Lacy's past become a way not just to link her with the killer, but also help to define who she is for the reader.
DC Lacey Flint is obsessed with serial killers. It's why she joined the force. The book begins with her failing to prevent the stabbing of a young woman who was attacked while Flint was fumbling for her keys in a hallway. She didn't see the attacker, a situation that doesn't impress the investigating officers. One of these happens to be DI Joe Joesbury.
An anonymous letter sent to a local newspaper points out the similarities between this killing and that of Jack the Ripper. (Oh, my God, I can hear you exclaim; not another one, but hold your disgust, Bolton handles this very well.) More I should not reveal lest I awake the spoiler police.
Bolton had written several stand-alone thrillers before beginning this series. I will have to take a look at some of them.