“Prisoner of Heaven” is the third book in Zafón's Cemetery of Forgotten Books series. While each book is intended to be a stand alone novel, meaning that the books may be read by themselves or the series may be read in any order, I'm not sure that this theory holds true for this particular book. There are a number of references to prior events that may not make sense to someone who hasn't read the other two novels. Granted, these references don't constitute much in the storyline, perhaps just a sentence or two, so it may be possible to read past them without losing any meaning. It's difficult to say since I have read the other books, so when a little reference of something from the past pops up I know what it pertains to. Someone else may have to chime in on this opinion.

There is one more book for me to read, however, “Prisoner of Heaven” might be my favorite book of the series. This is due mainly in part to the fact that we get to explore more of the backstory and history of my favorite character. I'm not going to mention their name as I want to continue writing my reviews by not giving away much plot.

So far this has been a great series of books and I'm looking forward to the finale.