In ruins on the outskirts of Gaza, the war-torn Palestinian city that had been a metropolis since the times of the pharaohs, a plucky young female archaeologist has made a remarkable find: possibly the earliest known image of the Virgin Mary, created during her lifetime. But before she can reveal it to the world, it is stolen from her in a brutal personal assault amidst the chaos of an Israeli airstrike. But who has stolen it and why? What dark hidden secret did it conceal? With her former lover, an Oxford professor of comparative historiography - the science of comparing alternative versions of the past - she sets out on a dangerous quest to some of the holiest sites in Christendom, from the plains of Bavaria to the mountains of central Spain and an ignored ancient temple in the heart of London. In a tale of murder, treason, intrigue and geopolitics, they uncover a web of conspiracy, cover-ups, confused mythology and interlinked religion that dates back to the last pagan Roman emperor, and maybe even to the very origins of life on earth. Astonishingly well-researched, this is a gripping yarn that is at the same time intellectually challenging. A book to make Dan Brown turn green with envy.