I just reread this book, it's really good! Allison's synaesthesia is really fascinating, It's really incredible the way she perceives the world around her. Allison is sent to a psychiatric institution for having a 'mental breakdown'. And she is being investigated for a classmate's disappearance, because she was the last one to see her, and she confessed to having killed her (she's not really sure if and how that happened). The book makes a tremendous upturn and we find out crazy things (can't get to much details without spoiling it)...