Tom Stoppard is perhaps the worlds leading funniest and cleverest playwright Ever since he hit the ground running in the 1960s with Rosencrantz and Guildenstern Are Dead there has always been a streak of melancholy beneath the sparkling surface of his work Now with his latest play Leopoldstadt he comes full circle and faces up to the pain and loss in his past In this programme he tells Alan Yentob his extraordinary story