The author of the blockbuster novel "The Da Vinci Code" faces an English High Court challenge Monday from two men who claim he stole their ideas. Michael Baigent and Richard Leigh are suing their own publishers, Random House, claiming Dan Brown's book draws heavily on their 1982 bestseller "Holy Blood, Holy Grail". Brown's 2003 book has sold more than 30 million copies worldwide and earned the American 45 million pounds (66 million euros, 78.5 million dollars) in one year, instantly making the writer one of the world's richest. Baigent's and Leigh's book tackles theories that Jesus and Mary Magdalene married,...