Ali Baba, Ou Les Quarante Voleurs (Ali Baba, or the Forty Thieves) is a French opera composed by early-19th century composer Luigi Cherubini. The story follows the almost universally renowned story from the Arabian Nights about a man who must protect his possessions from forty thieves. Ali Baba is one of the composers last works, and was oft-derided by the major musical critics and personalities of the time. Later, however, many came around to appreciating the work's generous experimentation with orchestration and texture in an effort by Cherubini to add character to the work's exotic themes.