The Lost Symbol — Dan BrownPRELOVED Famed Harvard symbologist Robert Langdon answers an unexpected summons to deliver a lecture at the U. S. Capitol Building. His plans are interrupted when a disturbing object artfully encoded with five symbols is discovered in the building. Langdon recognizes in the find an ancient invitation into a lost world of esoteric, potentially dangerous wisdom. When his mentor, Peter Solomon a long standing Mason and beloved philanthropist is