The song comes from Lionel Bart's musical Oliver, based on Charles Dickens's Oliver Twist, which opened in London in 1960 and became a hit film in 1968. In the story, Fagin, leader of a gang of child thieves, sings it while teaching Oliver and the other boys how to steal without being caught. The number became one of the show's most recognisable comic set pieces, and its catchy, old-fashioned charm has kept it in circulation in stage revivals, school productions and online edits that need an instantly recognisable shorthand for playful wrongdoing.