Not sure this book was 100% necessary. I bought it and read it because I'm a sucker for this series. I thought books 1 and 2 in The Dark Duet were flat out great and I was interested to see the world from Caleb's perspective. Was this book needed? Probably not. Did I enjoy the sixty plus minutes it took me to get through it? Yes. I felt the ending of book 2 was quite abrupt, this book helps fill in those gaps and fleshes out the story. Roberts probably could have just tacked this on to the end of that book, but I suppose that is why she just entitled this "Epilogue." What you see if what you get, if you liked the first two books you'll want to go ahead and read this.