This book is about a fireman (Boyle) who retires and then becomes a detective. He gets one last case before he retires, however it quickly spirals out of control as the people related to his case begin dying mysteriously. Some think Boyle is off his rocker since he continues to insist that they are being murdered even after being deemed suicides.
The primary focus of this book revolves around relationships between fathers and sons with most having similarities in their career paths. One son is a cop, the other a criminal, but both have seen their fair share of corruption under the influence of money which has caused them to lose sight of what was important. The family dynamic is interesting because both boys have formed attachments outside their family dynamic due to similar circumstances involving an uncle who wasn't involved in either of their lives.
The theme I found most interesting (which is humorous because it's also the name of the book) would be how World Gone By can create a world gone by between someone and someone else. Lehane uses this phrase to paint a picture that we all have people whose experiences we draw from, some good and some bad and many times we play them over and over again in our minds like movies. For example, when one character feels unattractive he reminisces on his relationship with his wife which later causes him to rekindle his relationship with her for a short period before realizing she was no longer the same person he married years ago. In another instance, father takes advice given to him by his own father and then goes on to give that same advice to his son who doesn't take it seriously. I suppose the author wants us to consider the idea of how our actions, good or bad, may shape others in some way.
This book is part of a series which was interesting because this book can stand alone based on what had happened before (in other words, Lehane writes each story with enough detail you don't need to read any others). However, there are references made toward things spoken about in other books like the mafia elements which haven't really been explored until now. I do understand that several books were published too closely together for me to get my hands on them at the time of reading World Gone By but I think the references could have been made a bit more subtly without revealing too much, or better yet, there was enough information given to get readers up to speed if they wanted to read the other books in the series.
Overall I would give this book 4 stars out of 5 for its complex theme and well-developed characters accompanied by a written storyline that's easy to follow. The only downfall is it took quite sometime for me to get through because it just didn't hold my attention as much as others have in the past.