Life for fourteen year old Alex is okay most of the time. He enjoys school, has a best friend Sam, and a pretty and only mildly irritating younger sister, Nicky. But then Sam starts acting strangely, and so does Nicky – and both insist on sharing secrets with Alex, making him promise not to tell anyone. Then Nicky goes missing and only Alex feels he knows where to find her. But is Sam anywhere around to help?