Loved! 
 There were small parts where it shone through as a YA book, but for the most part age didn't matter. 
 The story follows Emma as she discovers first that she has atwin sister, second when she slips seamlessly into Sutton (her twin)'s life, and third as she discovers that her sister is dead and someone close to her is the killer. 
 This is book one of a soon to be four book series and I am impatiently waiting for the rest of the books!