The neighboring kingdoms of Heartwood and Heartsong stand on the brink of war, and thirteen-year-old Evelyn holds the ancient legend that promises to reunite them. With the help of her Aunt Nora and the prince and princess of Heartwood, Evelyn must journey across the two kingdoms to fulfill the legend's decree. Yet with the scheming Demarco terrorizing them from the skies and the king of Heartsong captured and imprisoned, the group's chances of success feel ever more fleeting.