He saved the Catholic Church from a fundamentalist radical in Angels & Demons and exposed the world's greatest cover-up in The Da Vinci Code. Now, Harvard symbologist Robert Langdon is summoned to deliver an evening lecture in the U.S. Capitol Building. Within minutes of his arrival, the night takes a bizarre turn. A disturbing object -- artfully encoded with five ancient symbols -- is discovered in the Capitol Building. The object is an ancient invitation, meant to usher its recipient into a long-lost world of hidden esoteric wisdom. And when Langdon's mentor Peter Solomon -- a prominent Mason and philanthropist -- is kidnapped, Langdon's only hope of saving Peter is to accept this invitation and follow wherever it leads him. Langdon finds himself plunged into a clandestine world of Masonic secrets, hidden history, and never-before-seen locations... all of which seem to be dragging him toward a single, inconcievable truth.