Sixteen-year-old Jean "Jinx" Honeychurch, the descendant of a witch, must leave Iowa to live with relatives in Manhattan after the first spell she casts goes awry, but she will have to improve her skills to stop her cousin from practicing black magic that endangers them and the boy they both like.

Having moved to Annapolis, Maryland, with her medievalist parents, high school junior Ellie enrolls at Avalon High School where several students may or may not be reincarnations of King Arthur and his court.