TONY DITERLIZZI is a New York Times bestselling author who was awarded a Caldecott Honor for his cinematic version of Howitt's classic The Spider and the Fly. His art has graced the work of J. R. R. Tolkien, Anne McCaffrey, and Greg Bear. He and his wife reside with their pug in Amherst, Massachusetts.HOLLY BLACK was born in a decrepit Victorian house much like the one the Grace kids move into. Her mother gave her books on ghosts and fairies and Holly spent a happy childhood cooking up imaginary witches brew with her younger sister. Black is an avid collector of rare folklore volumes, spooky dolls, and crazy hats. She resides in Long Branch, New Jersey.