* From the [Introduction]

When we presented our discovery of the secret symbolism in Leonardo da Vinci's paintings in our 1997 book, The Templar Revelation: Secret Guardians of the True Identity of Christ, little did we realize that we were making a significant contribution to a remarkable phenomenon of the twenty-first century. Not only did our book directly inspire Dan Brown to weave his blockbuster The Da Vinci Code (2003) around the concept of da Vinci's love of hidden heresies and dangerous codes, but we were taken aback to realize that in doing so we had also assisted at the birth of a new, impassioned wave of interest in the truth about the origins of Christianity.

A central part of Brown's fiction is the notion that there exists an age-old French society, the Priory of Sion, whose task it is to protect the sacred bloodline of Jesus and Mary Magdalene -- the implications of which are truly shocking to those who remain true to the traditional teachings of the Church. The inevitable backlash against all the subjects raised in Brown's book has seen the Priory of Sion roundly trounced, dismissed once and for all as a straightforward hoax.

However, we became increasingly dissatisfied with either extreme -- complete acceptance of everything claimed by or on behalf of the Priory or blanket dismissal -- for two reasons. While there is evidence that the Priory is a modern creation, rather than the ancient and venerable secret society it is supposed to be, there is considerably more to it than a simple hoax. As our continuing research has found, the Priory really is important, but for rather different reasons.

This has given us the golden opportunity to present our ongoing investigation into the Priory of Sion. And unexpectedly, we found this work converging with other, quite independent, lines of research, specifically those that led to our 1999 book, The Stargate Conspiracy, which dealt with a little-known but extremely influential politico-occult movement known as synarchy. As we delved into it even deeper, we found ourselves unexpectedly back in the underground stream that also sweeps the Priory of Sion along. Even the research for our book on the "secret history" of the Second World War, Friendly Fire: The Secret War Between the Allies (coauthored with the late Stephen Prior, and Robert Brydon, 2004), became surprisingly relevant, as certain power struggles in wartime France provide an important backdrop to The Sion Revelation.

The second reason for our writing this book is much wider in scope, and to us more important: those who defend the traditional religious views against Dan Brown's book argue that if they can prove the Priory of Sion is a hoax, then the deeper issues -- such as the reality of the "forbidden" gospels, the relationship between Jesus and Mary Magdalene, and the centuries-long Church cover-up of such inconvenient evidence about the Christian religion -- can also be condemned and dismissed. This is utter nonsense.

Whatever else can be said about Brown's book, it has brought some fundamental questions about spirituality and religion to a massive and even secular international audience and sparked off far-reaching debates. It has even been pointed out that it has revived on a grassroots level the same bitter debate that raged in the formative years of the Christian religion. The major split was between the two fundamentally different visions of the faith: the Gnostic view, in which the individual forges his or her own relationship with God and is therefore responsible for his or her own salvation, and the priest-led faction that became the Church -- in which the Church alone holds the keys of the Kingdom. It is a battle that the Church believed long won, but now the fissure lines are reopening as the floor is cleared for either a new, informed debate or a fight -- and all due to the unlikely influence of an airport thriller!

Obviously, for some reason and in some mysterious way, Dan Brown has tapped into the prevailing zeitgeist, but this phenomenon can only exist because people have a deep inner need to excavate beneath the traditional religious certainties. But Brown is by no means its only popular manifestation. J. K. Rowling's young wizard Harry Potter scintillates with Gnostic daring, and -- as many commentators point out -- the movie series The Matrix draws directly on ancient Gnostic concepts, dressing them up as science fiction, with elements from the Priory of Sion's mythos also having pride of place. While The Matrix's sacred city of "Zion"/Sion is not unique to Priory lore, it is hard to find another source for the character called the Merovingian.

The true story of the Priory is rather different from Brown's version, but it is highly significant, disturbing, and even alarming. And it carries us along into a dark and intriguing world where a great many other uncomfortable facts, both religious and political, will have to be faced.