On her fifteenth birthday, Sophie Joiner finds out she is a Hexe, or witch, when her cat Mr. Mittens talks to her. Suddenly, magic cats start showing up after their Hexes have been killed. Now she finds herself attacked by medieval monsters, overwhelmed by orphaned Hexecats, and threatened by a murderous warlock. In order to survive, she must unlock the spells held by the magical cats while keeping both the Hexecats and her powers hidden from her foster parents. Sophie calls on the Itty Bitties, her best friends and soccer teammates, as the only people she can trust. Without their help, she could be the next one dead.