A British court this week took up a lawsuit brought by two British historians who claim that the international best-seller The Da Vinci Code plagiarized their work. Michael Baigent and Richard Leigh say that American author Dan Brown stole the most compelling ideas in his novel from their earlier nonfiction book, Holy Blood, Holy Grail. That book advances the controversial theory that Jesus married Mary Magdalene, and that they had a daughter whose descendants married into a line of French kings. The novel follows a similar line. It is not as though Brown has simply lifted a discrete series of raw facts, said a lawyer for the two historians during his opening argument. He has lifted the connections that join the points up. Brown concedes that he read Holy Bloodindeed, his novel cites it directly at one pointbut he argues that history cant be copyrighted.