The mystery is a bit lacklustre. It's never particularly intriguing, and the final reveal is neither the missing piece that makes it all make sense nor a twist, it's just some more of the story, I guess. But the biggest problem with the book is the excessive focus on the protagonist's dead fiancée and his resultant ennui. It's unnecessary and transparent; a textbook example of women in refrigerators.

Those points aside, the book is mostly fine. I'll probably read the second one, at some point, since I have it as well, but I'm not in any rush to get to it. For a first book, it shows promise, so if his later ones improve on it they'll be worth getting to. And the dead fiancée does seem to be basically dealt with as a motivating factor at this point so hopefully there won't be so much of that in the later ones.