 Jake s little sister is about to lose her first tooth. But since it s a dragon tooth, it has mystical powers. The Tooth Fairy s assistant, Dr. Diente, has been biding his time until a dragon tooth came along. Seizing his opportunity, Diente grabs the Tooth Fairy s wand and goes after Haley. But he didn t figure on a mystical shield guarding the Long house, as well as the American Dragon.