From Goodreads: Former paramilitary killer Gerry Fegan is haunted by his victims, twelve souls who shadow his every waking day and scream through every drunken night. Just as he reaches the edge of sanity they reveal their desire: vengeance on those who engineered their deaths. From the greedy politicians to the corrupt security forces, the street thugs to the complacent bystanders who let it happen, all must pay the price.
This review will contain some spoilers because I found it very difficult to express some of the things I didn't like without actually saying what those things were. None of these spoilers are too big and I won't say how the book ends but they may answer some questions before you read the book.
This book is different from anything that I have read before. The clear (or not so clear) like between good guys and bad guys that usually more or less appears in most books is absent here. What you have is a main character and his antagonists.
One thing I liked is that the ghosts are not metaphorical. Fegan sees the ghosts that haunt him when he's awake, even though the rest of the people can't. While I liked that the ghosts are not just a way of explaining the main character's guilt, I thought it was a bit disappointing how unghosty they are. It's never really clear whether the ghosts are real or just in Fegan's head (although at one point someone else mentions one of the ghost as if she could see it), but even though they appear a lot, they never do anything. Sure, they are the reason for the plot, but other than this, they're just there.
What I did not like so much was that I never felt that there was any suspense about what was going to happen. By the time I reached the end of the book, I had the impression of having read about four hundred pages where not many things happened. The plot includes a lot of things, but because of the lack of intrigue, it can look like you have read a lot of pages where the plot did not move much.
The book is not bad and the premise is great, but after reading the summary, I was expecting something a bit different.