In this number, Harold Zidler and the Moulin Rouge performers improvise the pitch for their new show to secure the Duke’s investment. Their pitch is set to “Galop Infernal” from Jacques Offenbach’s 1858 opera Orphée aux Enfers (Orpheus in the Underworld). “Galop Infernal” is one of the most recognizable songs written for the can-can, the energetic and provocative dance that became popular in dance halls (including the real-life Moulin Rouge, where it originated) in the 1830s and 40s.