Jane and Timothy Dawes meet up in a park to plan their lives soon after their graduation. Deciding that Timothy must take the first job he's offered, a passing tramp offers them £7 a week to look after his mobile piano. Upon accepting, they discover that when the piano plays it delivers all within earshot an irresistible desire to dance! After attempts to ban the music by the Ministry of Pleasure and Pastimes, the piano vanishes, and Timothy enlists his Uncle Zed to take them in his flying saucer to retrieve it. *Parts are usually double cast.