That film IS my favourite film of all time! Absolutely superb acting, plot and the cars add a certain je ne sais quoi to the entire proceedings. And it's so almost true, too! So THAT'S why we weren't allowed to join the Common Market in 1967....!
I love the film SO much I looked up the hotel where the Jackal seduces the Countess, but it was a little too pricy for a weekend away!