Seventh Street Books sent me a copy of this book for review (thank you). It has been published so you can find a copy in your local bookstore now. This is the third in a trilogy, so you might want to get the first two and read them in a series.
When he and his partner are on a call, the partner is driving and Sean feels something clip the mirror but he doesn't see anything in the dark. Turns out it was a person they clipped and the other cop says Sean was the driver. That's enough to let the top cop do what he's been wanting to do for a long time: Make Sean retire. Sean's not happy but he can't do much about it. He certainly never expected to get recruited by M15!
The big reason is because he knows the man they are trying to find. He used to be friends with him. He wanted to join the IRA with him, but Dermot refused to let him. That's how he became a cop. Now they want him to find Dermot before he bombs something else. Sean is willing to try but he knows no one will disclose his whereabouts to a cop. He's right. But someone is willing to trade information.
It seems Dermot's mother-in-law wants to know who killed her youngest daughter. It's a cold case, a locked room mystery, and he's not supposed to be off on another case. However, it may be the only way to find Dermot.
The investigative work on the young woman's death is fascinating. Watching Sean use his knowledge of how the IRA works and trying to work ahead on Dermot's plot is also intriguing. Some parts of the plot I anticipated, some I did not. It's a well worn trail with folks on all sides being no better than they should be. It ended how it had to. Some sad, some happy, and some just glad to be alive. Sean was walking alone with the story started and that's how the story ended, too. He's not unhappy, though, and that's what counts.