Historian David Olusoga examines fifty years of BBC documentary archives to try and discover why dictators can have such a powerful appeal and asks if our fascination has fed their power. He uses the examples of, arguably, the first dictator, Julius Caesar, and modern equivalents, who either repeated or learned from his mistakes, like Benito Mussolini, Adolf Hitler, Fidel Castro, Muammar Gaddafi, Saddam Hussein and Zimbabwe's Robert Mugabe.