Boris Johnson travels to France, Spain, Egypt, Israel, Syria and Turkey to continue his investigation into the early beginnings of what some people now call 'the clash of civilisations'. He begins by looking at the crusades, and the way they are viewed in the west and in the Muslim world today. But Boris finds that the realities of the crusades are far more subtle than modern attitudes to them would have us believe. As with many current entrenched positions about the so-called 'clash of civilisations,' such attitudes are often a rewriting of history in the light of later events. London's mayor also looks at the Sack of Constantinople, when Latin Christians fought eastern Christians, leading eventually to the fall of the city to the Ottoman Turks in 1453. He looks too at the Reconquista in Spain, which culminated in the wholesale expulsion of Jews and Muslims. At every turn of his journey, Boris Johnson finds that the real history is a good deal more subtle and interesting than the fictions that have grown up around it.