Agnes Herne, known back at home as Karonhisake, or Searching Sky, is living in Boston and beginning college when she reads a book that changes her life. Although Agnes cannot be sure, she suspects a connection between the girl described in the story -- Mary Newbury, a seventeenth-century self-professed witch -- and one of her own ancestors, a medicine woman whom Agnes's aunt still honors in storytelling and whose personal artifacts are treasured by the family.
Agnes begins to contact the web address listed at the back of the book, but before she can do that, someone contacts her. Agnes undergoes a powerful and frightening experience. It is as if she is living events from the long-ago past, but is it a vision or a dream? As impossible as it seems . . . could it be a message from Mary?