While truant from school, young siblings Jeremy and Jemima meet the beautiful Truly Scrumptious (Sally Ann Howes), who falls for their widowed father, Caractacus Potts (Dick Van Dyke), and his various oddball inventions, including the family's noisy rebuilt car, Chitty Chitty Bang Bang. One day at the beach, Caractacus tells Truly and the children a fanciful fable about the villainous Baron Bomburst (Gert Frobe) and his evil designs on the Potts family car.