After fifteen-year-old Simon Porte's family is killed in an automobile crash, his father's brother whom he's never met brings Simon to live with him and his wife in upstate New York. Simon doesn't trust Uncle Raymond, and for good reason. Raymond is dying and using his powers to take over Simon's body. Simon and his allies—his dotty great-aunt Lucinda, his sister whom he finds living with another relative, and a pair of odd twins—wage war against the evil Raymond and his cronies.