Bullied at school about his stutter, and feeling ignored at home by his mum, stepdad and stepsister, Thomas takes off to the beach with the family dog, Lucy. The dog begins barking outside a cave. Bold enough to investigate, Thomas finds an injured dragon. He is frightened at first but something about the dragon's eye reassures him and invites him to come closer. A friendship is sparked. Determined to help the dragon he's called Puff, Thomas confides in his friend Huhana, who to his surprise doesn't dismiss his dragon as make-believe and tells him about Māori taniwha, some of which were believed to act as protective guardians. The dragon flies Thomas to visit his estranged father, and he learns about the accident that caused his stutter. As Thomas gains confidence throughout the story, with the help of Huhana and Puff, he stands up to the bullies and helps uncover an illegal logging operation that threatens the town. As his confidence builds, he loses his stutter and his need for the dragon dwindles.