As soon as I saw the strange text on page 298, I headed STRAIGHT for a mirror
Langdon and Teabing are thinking too hard. 
After coming to terms with my oblivion of the
Fibonacci numbers
"O, Draconian devil! Oh, lame saint!,"
Considering the message's text, I'm guessing that the magic letters are S-O-P-H-I-E.
Why not? It even rhymes with the message.
Why not? It even rhymes with the message.