It's said to have been re-written up to 300 times in 40 years... Francis Ford Coppola's "Megalopolis" finally premiered in Cannes on Thursday, with star Adam Driver on the red carpet. The director won the festival's top prize – the Palme d’Or – in 1974 with "The Conversation" and then a second time in 1979 with the now legendary "Apocalypse Now".