Despite a slightly understated title, this was an amazing novel.
Cass and her younger sister are killed in a terrorist bombing, only...Cass isn't quite dead. She becomes a vapour-like entity that must live in the minds of others in order to survive, and despite her helplessness, she finds herself drawn in to a situation that possibly only she can prevent, and in doing so might just be able to save herself. The themes of death, greif, life beyond death and the resiliance of humans were spun together to create an amazingly insightful, refreshing book. The different minds of the characters that Cass visits make an interesting balance. Definitely get this book.