Twelve-year-old Sophie Wu, a young witch who aspires to learn magic and attend the Royal Magic Academy, is sent to live with relatives she's never met to train for her entrance exams. However, the training isn't going well so Sophie, impatient to begin casting spells, steals her cousin's spell book and attempts magic on her own. The spell goes wrong and Sophie causes a storm that washes her out to sea. She is saved from drowning by a young water dragon named Lir, but in the process, Sophie accidentally entangles her magic with Lir's causing him to be trapped on land in human form without memory of where he came from. With his magic, Sophie could pass her entrance exams, but that would keep Lir from regaining his memories. Sophie must prove to herself--and to everyone else--that she can pass the exams without Lir's help, and find a way to separate their entwined magic.