This is quite a short book but I still finished it in record time as you just want to find out more about the characters, and it is an easy read. I'm not quite sure what I expected from this book after reading the cover but didn't expect it to be such a dark tale, because dark it is; while there are streaks of black humour in it, it can be pretty depressing. About 3/4 through the book, Alison does something (or intends to do something) which makes you dislike her, and after that I didn't really care for what happened her that much.
The reason I only gave this three stars is that it becomes quite obvious from early on who killed the Cowpers, and because it is a very dark book, which I didn't really expect it to be. But I would still recommend it as a quick in-between other books read.