Twelve-year-old Emily Timmons is tired of being upstaged by her confident and capable younger sister. Charlotte Amelia, on the other hand, idolizes her big sister and follows her everywhere, including to Emily’s special treehouse. When a freak earthquake transports the girls from the treehouse to a magical land, Charlotte Amelia is captured by an evil Imp queen. To save her sister from the queen’s cruel clutches, Emily must swallow her fear and perform nine treacherous tasks, one task for each year of her sister’s life. As Emily’s quest progresses, however, she and her new friends begin to suspect that the Imp queen may only be using the girls as part of a larger, wicked plan. Emily must find courage within as she braves sea serpents, dragons, giants, and other creatures in exchange for her sister’s freedom.