An eccentric inventor, Caractacus Potts, lives with his two children, Jeremy and Jemima, and his equally peculiar father. Struggling to make ends meet while pursuing his imaginative inventions, Potts stumbles upon a broken-down race car. After his children express their affection for the car, he decides to restore it, using his ingenuity to turn it into a marvelous, magical vehicle that can fly and float, much to the delight of his children. They name the car based on the unusual sounds it makes - sounds that seem to herald the beginning of their extraordinary adventures.

During a picnic with the car, they tell a fantastical tale involving the car and a faraway land ruled by an evil baron who has outlawed children. Their story is interrupted when they mistakenly believe their fantasy has become reality, leading to the bewildering appearance of a beautiful young woman, Truly Scrumptious, the daughter of a candy factory owner. Together, the group embarks on a whimsical journey in the magical car, where they find themselves drawn into a real-life adventure in a distant land. Their journey brings them face to face with eccentric characters and challenging situations that test their courage and ingenuity, all while they try to evade the clutches of the villainous baron and his minions who are determined to capture the car for their own nefarious purposes.