On page 234 of The Da Vinci Code, the book alleges that the discovery of the Dead Sea Scrolls and the Nag Hammadi texts are proof that more than 80 authentic gospels existed which said Jesus was merely human. Dan Brown strikes out on these claims.
First, the scriptures found in the Dead Sea Scrolls are Old Testament texts that have nothing to do with the New Testament gospels. So the number of gospels discovered in the Dead Sea Scrolls was zero. (Strike one!)
Second, the Nag Hammadi texts had 45 titles, only five of which were gospels: The Gospels of Truth, Thomas, Philip, Egyptians, and Mary. All of these writings dated from the second to third century, much later than the New Testament gospels. (Strike two!)
Third, all of these later gospels taught a heresy known as Gnosticism, which denied that Jesus came in the flesh. Rather than showing Jesus to be a mere human, the Gnostic gospels actually deny his humanity! (Strike three! Dan Brown, you're out!)
(For more information, see Darrel L. Brock, Breaking the Da Vinci Code. Nashville; Nelson Books, 2004, 61-64.)