Renowned Harvard symbologist Robert Langdon is invited to give a lecture at the United States Capitol, at the invitation apparently from his mentor, a 33rd degree Mason named Peter Solomon, who is the head of the Smithsonian Institution. Solomon has also asked him to bring a small, sealed package which he had entrusted to Langdon years earlier. When Langdon arrives at the Capitol, however, he learns that the invitation he received was not from Solomon, but from Solomon's kidnapper, Mal'akh posing as Solomon's assistant, who has left Solomon's severed right hand in the middle of the Capitol Rotunda in a recreation of the Hand of Mysteries. Mal'akh then contacts Langdon, charging him with finding both the Mason's Pyramid, which Masons believe is hidden somewhere in Washington, D.C., and the Lost Word, lest Solomon be murdered.