I really enjoyed the story though I was really not liking Warrick in the beginning. He really was undermining Fallon's life in every possible way. First, he was ruining her cover. Then revealing her to very dangerous people as bait. Only when he became attached, did he want to use her as bait as a last resort? Too late buddy, you already put her in danger and pretty much ruined her life as she knew it.
I'm not too sure about the ending either with Warrick's parents. Yes, it was nice but not sure I found it believable. The PTSD episode at the very end was rather high handed and considering he's still a relatively active operative, it would also make the degree he was suffering from PTSD bit hard to swallow. Granted, there is the personal factor involved but still it just didn't work for me even if it did pave the way for Fallon in other respects.
Okay with that off my chest, the mystery and intrigue of this story was engrossing. I couldn't wait to find out what was going on. Fallon is a sensible and tough as nails character. She also was not the total headstrong idiotic heroine you generally find in a lot of these novels. I also love how Lily's past is slowly being revealed and setting up for the last book in the trilogy (I'm assuming is a trilogy).