As Cassie begins her junior year in high school, she comes into contact with a group of unlikely friends.
They're all children of witches, and explain to Cassie that her mother was a witch too.
And with Cassie in town, they now have a full "circle" of six members, meaning their powers have increased dramatically.
Inside the book is a message to Cassie explaining that she kept their real family history and her powers a secret in order to keep her safe; as the circle soon finds out, their powers attract dark and dangerous attention that constantly puts them in harm's way.
The show first premiered on September 15, 2011 and was cancelled on May 11, 2012 after only one season with 22 episodes.
Initially Cassie refuses to believe that she is a witch, even after Adam helps her to unlock her powers.
It is only after she discovers an old leather-bound book of spells left to her by her late mother, Amelia, that Cassie begins to accept her power.