The team accepts a mission to destroy the book Daybreak, which the client (the son of the deceased author) holds responsible for his father's ruined life. Lucy discovers a secret message in the book: the author was forced by the corrupt Duke Everlue to write it for three years in isolation before committing suicide. She persuades the client to keep the manuscript, which is actually a memoir dedicated to his son. Later, Natsu and Gray are approached by Erza to stop the dark guild Eisenwald, which wants to use the cursed flute Lullaby for an assassination.