"The Secret Circle" is a supernatural drama series based on the book series by L.J. Smith. It follows a teenage girl named Cassie Blake who moves to the fictional town of Chance Harbor, Washington, after her mother's mysterious death. There, she discovers that she is part of a secret coven of witches and has inherited powerful abilities. As Cassie navigates her new life, she learns about the complexities of witchcraft and the dangers that come with it. The coven, made up of her new friends, faces various challenges, including rival witches and dark forces that threaten their existence.