Dan Brown in the Da Vinci Code (copied from The Passover Plot) got the story of Jesus descendants from a Gnostic heresy a few hundred years after Christ.
King Arthur was a real king of France and England. He was a Black Jew and Catholic Knights Templar. He was about 12 feet tall a descendant of the Nephilim. His skeleton was dug up in the cemetery at Glastonbury a Pagan worship sight for the Megalithic builders.
He and his knights went to Jerusalem in the first part of the Crusades to locate the treasure buried by the Jews in 70 AD when the Romans scattered them, the treasure was recorded in the copper scroll hidden by the Pagan Essene Gnostic cult at Quran. Arthur had this same information on the whereabouts of the treasure. These knights found the treasure and went back to Europe and established banks to control Europe and establish the World Government and planned to use their riches to re-establish the Pre-Flood world government of Cain destroyed by God in 2347 BC by a worldwide flood.
These knights planned to create a world government that had been destroyed by God a second time under the direction of Nimrod of Babel about 1900 BC. Nimrod was of the bloodline of the Serpent the Nephilim which became commonly known as the Illuminati.
The Grail represents the Grail Treasure hidden by the Knights Templars (These Knights Templars are the highest Scottish Rite Freemasonry refounded in 1776 in Washington DC led by George Washington a Mason) The Grail was to be used to fraudulently confirm the bloodline of the future Antichrist to Jesus. The Antichrist's blood type will be the rarest AB Negative the same as the founder of the Knights Templars Jacques de Molay, found on the Shroud of Turin, falsely claimed to be the image of Jesus. Obama has this same rare blood type, as do many rich and powerful descendants of royalty, the Illuminati Families.