April and the Extraordinary World

Avril et le monde truqué is a movie starring Marion Cotillard, Marc-André Grondin, and Philippe Katerine. It's 1941 but France is trapped in the nineteenth century, governed by steam and Napoleon V, where scientists vanish...
France asleep in the nineteenth century, governed by steam and Napoleon VI, where scientists vanish mysteriously, a girl, Avril, goes in search of her missing scientist parents.