‘We'll always have Paris,' Humphrey Bogart assures Ingrid Bergman in the oft-quoted farewell scene from Casablanca in which Bogart's character, hard-hearted restaurateur Rick Blaine, bids former lover Ilsa Lund goodbye. The backdrop against which they first fell in love, Paris later serves as a reminder of their deep mutual longings. And with a host of different realisations by filmmakers from Philip Kaufman to Julien Leclercq to Woody Allen, there...