Five years have passed since Victoria abandoned life as a spy and started taking care of Nonna alongside her husband, Jeffrey. After returning to the kingdom of Ashbury and reuniting with her friends, Victoria comes into possession of a rare book titled The Lost Crown. It isn't just any old tome, however--it contains a hidden code, one that proves to be no match for her experience with decryption. The message points to a treasure hidden somewhere in Sybil Forest, and although Victoria knows she should prioritize her life with Nonna and Jeffrey, she finds herself dreaming of hunting for the prize. Fortunately, her husband and daughter want nothing more than to support Victoria in her desires, and soon, they are off treasure hunting together. Thus begins a grand adventure full of twists, turns, and even a secret about the Ashburian royal family.