In the Tintin books by Hergé, the opera singer Castafiore always sings "The Jewel Song" from Faust by Charles Gounod. If fact, she never sings anything but "The Jewel Song" from Faust. In the Tintin movie, however, Castafiore does not sing her signature song; rather, she sings something from Romeo et Juliette, which is another opera by Gounod. Seven years later, I still wonder why the movie makers decided to change her quintessential song from one opera by Gounod to another. Was it lazin...