It was a long time ago when I read The Summoning but I remember the action picking up as soon a Chloe got out of her apartment, when she saw a ghost. 
 I guess I expected something similar here, only I didn't get that, and I am still trying to figure out how this makes me feel, dissapointed or not. 
 Of course it's about a differet sort of power, but still, it felt really slow to me, as the interesting part for me began somewhere in the middle, probably when they found Mina's body. 
 Otherwise, I love it, especilly the world(island) the author has created, and the way everyone was trying to protect a secret from Mina, even though they had no idea what secret they were keeping. 
 All the characters feel real to me, and I like how Maya isn't some whiny 16 year old, but a mature well developed one. I love her relationship with her parents, you don't get a lot of that in YA books(Example: Fallen, Twilight, Iron King, Hush Hush, ect.)and I love how they can be a real laugh and a strict parents at the right times. 
 I still haven't finished it, but I am expecting a cliffhanger! 
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 I am done now, and all I can think is why did I read it at all. I mean, what is the mystery? What is the point? Maybe the author had an idea about the island and the book, but she didn't quite pull it through.