Laura loses her little brother in earthquake-scarred Christchurch. A decrepit old man marks the child's hand with a noxious stamp. Jacko sickens quickly while the man grows younger. The doctors insist Jacko needs a bone marrow transplant - and Laura is the only donor. But Laura becomes convinced a mysterious older boy can help her "change over" and become a witch, defeating the evil spirit sucking the life out of her brother.