Billy Fisher (Tom Courtenay) lives in Yorkshire with his parents (Wilfred Pickles and Mona Washbourne) and grandmother (Ethel Griffies), and works as an undertakers' clerk overseen by the rigid Mr. Shadrack (Leonard Rossiter). Billy wishes to get away from his stifling job and family life. To escape the boredom of his humdrum existence, he constantly daydreams and fantasises, often picturing himself as the ruler and military hero of an imaginary country called Ambrosia. He also makes up stories about himself and his family, causing him to be nicknamed "Billy Liar".