The Shroud of Turin, widely thought to be a fake, is in fact authentic. The greatest mystery in history is finally solved, in Thomas de Wesselow's The Sign.

The birth of Christianity, nearly 2000 years ago, has shaped the whole course of human history. Yet historians still cannot explain how it all really began. What made Jesus's followers claim to have seen him alive again, three days after his crucifixion? Why did Christianity take off so quickly?

It is one of the biggest and most profound of all historical mysteries. This extraordinary book, based on seven years of secret research by a brilliant historian, finally provides the answer. And it lies an enigmatic relic long assumed to be a fake: the Shroud of Turin.

With historical detective work and cutting-edge scientific research, art historian Thomas de Wesselow has discovered that Jesus's followers did see something at the tomb. They saw something real but out of the ordinary - something that seemed like a miracle. It was the burial cloth of Jesus, stained with his body image. This ancient marvel was hailed as a sign of the Resurrection, and kick-started the Christian faith.

The Sign details conclusive evidence that the Shroud of Turin is authentic, showing that the faint image on the cloth was formed naturally through a rare chemical reaction. It then explains how this revelation solves multiple puzzles of religious history: for example, the Gospel reports of the appearances of the Risen Christ are clearly based on early viewings of the Shroud.

As well as a major historical breakthrough, The Sign is a truly thrilling read - and one you will never forget.

'Overturning 2,000 years of received biblical wisdom is no small matter. Consequently [this] book encompasses an impressive amount of scholarship and scientific examination. Persuasive... a very intriguing explanation' Michael Prodger, Mail on Sunday

'Fascinating...startling' Telegraph

' A fresh insight into the Easter story' Financial Times

'Thorough, well-researched and fair-minded... Persuasive... much more than just an addition to the canon of Shroud literature' Irish Times

Thomas de Wesselow earned his MA and PhD at London's Courtauld Institute, researching the controversial Guidoriccio fresco in Siena, before becoming a Scholar at the British School in Rome where he worked on another of the great mysteries of Italian art history, the Assisi Problem. After a year in the curatorial department at the National Gallery in London, he was appointed a Post-Doctoral Research Associate at King's College, Cambridge, where he was later awarded a Leverhulme Early Career Fellowship. He has written on a number of famous Renaissance pictures whose meanings have hitherto defied analysis, including Botticelli's Primavera and Titian's Sacred and Profane Love. He has also developed new ideas about medieval world-maps, in particular the Hereford Mappamundi. Since 2007 he has been researching this book full-time. He is 40 years old and he lives in Cambridge.