Thirteen-year-old Connie Lionheart is the only universal companion, able to communicate with all of the mythical creatures hidden in our world. She is the most important member of a secret society sworn to protect the bonds between humans and creatures. But even Connie doesn't know the full extent of her powers.

And now, something dark is calling to her, taking her places and making her do things that she can't control. The Society doesn't believe her claims that these destructive acts are not her doing. With nowhere to turn, Connie escapes to a world deep underground, willed with others that the Society has abandoned.