Twelve-year-old Rowan is destined to be Queen; her twin brother, Rhydd, to be Royal Monster Hunter. Rowan would give anything to switch places, but the oldest child is always next in line, even if she is only older by two minutes. She resigns herself to admiring her monster hunting aunt's glorious sword and joining her queen mother for boring diplomatic teas. But tragedy shatters the longstanding rule, and Rowan finds herself hunting the most dangerous monster of all: a gryphon.