The Marquis theme was part of early discussions between Rael and Director Tony Fabian. In this video, Rael explains where the concept for the theme comes from, and how its applied in the film. He also goes into some detail about how the theme evolves to reflect the souring of Ada and the Marquis’ relationship.

Although the theme is hinted at earlier in the film (when we first meet the Marquis, the fullest sounding of the theme is in 4M36 A Thousand Apologies where Ada and the Marquis go on a date in the flower market.