When sixteen-year-old Lily Willison and her friends Nikki, Arielle, and Grazia start up a girls' soccer club and name their team the Weregirls, they soon find themselves drawn into a battle between good and evil. Lily's father, a supernatural guardian, makes contact with Lily after his death and reveals that she has magical powers—as do her friends.

As the girls learn more about their powers, they inadvertently awaken the Breed, sworn enemies of the Weregirls. To fight the Weregirls, the Breed Master calls upon Lily's soccer rival—the rich, conceited, and arrogant Andra Hewlit. Desperate for powers of her own, Andra will do anything she can to destroy Lily and the Weregirls....