The Vatican, once a powerful and territorially large, is now a tiny state of less than half a square kilometer. Nevertheless, he remains the spiritual and moral authority for around one billion Catholics worldwide. Sir Peter Ustinov explores this fascinating world with its ancient roots. He roams through grottoes and archives, tells of important places in Rome, Constantinople and Avignon and meets historical figures such as Charlemagne and Luther ... Episodes: 1. From the beginnings to Charlemagne 2. From Francis of Assisi to Leonardo 3. From the Reformation to the Modern Age