The Mountebanks is a comic opera in two acts with music by Alfred Cellier and a libretto by W. S. Gilbert. It was first produced at the Lyric Theatre, London, on 4 January 1892, for a run of 229 performances. It also toured extensively, had a short Broadway run, in 1893, American tours and Australian productions. The original cast included Geraldine Ulmar, Frank Wyatt, Lionel Brough, Eva Moore and Furneaux Cook. The American cast included Hayden Coffin and Lillian Russell. Despite its initial success, the work has been rarely revived professionally since the First World War, although the Lyric Theatre Company of Washington D.C. recorded it in 1964.
The story of the opera revolves around a magic potion that transforms those who drink it into whoever, or whatever, they pretend to be. The idea was clearly important to Gilbert, as he repeatedly urged his famous collaborator, Arthur Sullivan, to set this story, or a similar one, to music. For example, he had written a treatment of the opera in 1884, which Sullivan rejected, both because of the story's mechanical contrivance, and because they had already produced an opera concerning a magic potion, The Sorcerer. The idea of a magic potion that changes human behavior has long been a common theme of literature and opera. The device allowed Gilbert to explore "how people behave when they are forced to live with the consequences of their own actions."
The Gilbert and Sullivan partnership and their Savoy operas dominated the London musical stage from the late 1870s to 1890. When that partnership temporarily disbanded, due to a quarrel over finances after the production of The Gondoliers, Gilbert sought another composer who would collaborate on the idea that Sullivan had repeatedly rejected. He eventually found a willing partner in Alfred Cellier, a logical choice for Gilbert. The two had collaborated once before (Topsyturveydom, 1874), and Cellier had been the music director for Gilbert and Sullivan's early operas. Cellier had also achieved much success apart from Gilbert and Sullivan, particularly with his comic opera Dorothy (1886), a smash hit. It played for over 900 performances, considerably more than The Mikado, Gilbert and Sullivan's most successful piece. Dorothy set and held the record for longest-running piece of musical theatre in history until the turn of the century.