In the kingdom of Raine, a vast realm at the edge of the world, an orphaned baby girl is found by a palace librarian and raised to become a translator. Years later, the girl -- named Nepenthe -- comes in contact with a mysterious book written in a language of thorns that no one, not even the wizards at Raine's famous Floating School for mages, can decipher. The book calls out to Nepenthe's very soul, and she is soon privately translating its contents. As she works tirelessly transcribing the book -- which turns out to be about the historical figures of Axis, the Emperor of Night, and Kane, his masked sorcerer -- the kingdom of Raine is teetering on the brink of chaos. The newly crowned queen, a mousy 14-year old girl named Tessera who wants nothing to do with matters of state, hides in the woods as regents plot revolution. The queen's destiny, however, is intertwined with Nepenthe's ability to unravel the mystery of the thorns.