Undercurrent - Paul Blackwell * Actual rating is 3.5 stars.I love YA books told from a male POV. I really think there need to be more of them. Especially ones that the voice is so well done like this one was.I'm also really enjoying reading alternate reality/alternate universe books. This one was really great in that it was an alternate reality, but it was really focused on the one that Callum is in, and doesn't switch back and forth between them. I do tend to get a little confused trying to keep things straight so this was very refreshing for me. I also loved the mystery element of it all, even though I figured out what was happening pretty early.The main character is Callum, and I really liked getting to know the real him (at least the one that we are currently in the head of). I also thought it was neat to get to know the alternate him who is totally different from who he is in his original reality. He is totally confused though. He wakes up in the hospital and soon discovers that things are very, very wrong. He has no clue what is going on, and slowly needs to figure things out. I thought that he made some really stupid decisions, but he managed. I liked that because he seemed very realistic to me. He messes up, he's insecure about things, he's scared. It makes me believe it more.There's not really much more I can say about the story, but it was really great. There was a good mystery and thriller element to it, and even though it was alternate reality, it wasn't really focused on that except when it was important and necessary to the story. I also liked how it ended, and I hope that a sequel is made for it because I would love the story to continue. I thought that how we get Callum's memories from his other reality and then it goes into his current reality was done really well.It gives a well rounded story of how different Callum is in each one, and the reasons why he is. This was great!! * An advanced copy of this book was provided by the publisher in exchange for an honest review. I did not receive any compensation.