Following an ancient pilgrimage route a thousand miles from Canterbury to Rome, the bestselling and award-winning writer weaves history and culture into an exploration of why Christianity is struggling in the world it created. He is accompanied by fellow pilgrims and by the towering figures of the faith: Joan of Arc, Henry VIII, Martin Luther. The goal: walking to Saint Peter's Square over the old Roman road, in hopes of meeting the pope who is struggling to hold together the world's 1.3 billion Roman Catholics.