N othing prepares you for the shock that is the Cannes film festival: the adrenaline, the fatigue, the elation and the emotion, but also the hunger, the anger, the magic and the ridicule. For young cinephiles, and for almost everybody who works in the film industry, it is the mecca of cinema and has been so for nearly eight decades. Anyone going for the first time this week, as I did 25 years ago, should not listen to the old grognards – Cannes’ battle-worn veterans – who will lament that the festival has become an abominable circus and swear this year will be their last. It is a circus, and you can bet they will be back for as long as their knees can take it. For there is nothing quite like it. Born to counteract Benito Mussolini’s Venice film festival, its first edition was planned for September 1939, but Adolf Hitler had other plans.…