An historical document purporting to give a complete family history of Jesus and other biblical figures has been found at Wales' national library.
The book gives family trees and biographical details of biblical figures
The manuscript, believed to date from the 17th Century, has been likened to something which could appear in the best-selling novel The Da Vinci Code.
It is being analysed by experts at Christie's auction house in London.
The document was put into storage at the library about 50 years ago by its owner, Llandovery College.
The independent school, in Carmarthenshire, had placed half of its archive in the keeping of the National Library of Wales in Aberystwyth.
The manuscript only came to light after college warden Peter Hogan asked to see some of the books, and was told about its existence.
The first half shows the family trees of certain people in the bible, while the second lists every individual mentioned along with biographical details.
It appears to have been written by a man called William Spenser, who was not a cleric.
Mr Hogan said: "What he claims he has written is a complete genealogy of Jesus Christ.
"It is painstakingly researched. It is just a phenomenal piece of literature."
"I'm slightly nervous thinking about what it is worth," said Mr Hogan.
"I would imagine it will have a very, very high commercial value. The difficult decision I have got to take is whether I am willing to exploit that."
He compared the book with something which could have featured in the plot of the best-selling Da Vinci Code by Dan Brown, which includes suggestions that Jesus and Mary Magdalene married and had children, claims dismissed by historians.
"With The Da Vinci Code hot at the moment I very quickly flicked to the 'M' section.
"This section claims that Jesus rid Mary Magdalene of seven demons and as a consequence she then became an assistant of his.
"Then there is a whole section crossed out which is quite mysterious," said Mr Hogan.
He added the manuscript's margins contained anecdotal information about Mary Magdalene, which he could not find in the bible.
The 594-page manuscript was bought for £13 about 170 years ago by Thomas Phillips, the surgeon who founded Llandovery College.