When the NSA's invincible code-breaking machine encounters a mysterious code it cannot break, the agency calls its head cryptographer, Susan Fletcher, a brilliant and beautiful mathematician. What she uncovers sends shock waves through the corridors of power. The NSA is being held hostage...not by guns or bombs, but by a code so ingeniously complex that if released it woud cripple U.S. intelligence. Caught in an accelerating tempest of secrecy...

Harvard professor of symbology Robert Langdon awakens in a hospital in the middle of the night. Disoriented and suffering from a head wound, he recalls nothing of the last thirty-six hours, including how he got there . . . or the origin of the macabre object that his doctors discover hidden in his belongings. Langdon's world soon erupts into chaos, and he finds himself on the run in Florence with a stoic young woman, Sienna Brooks, whose clever maneuvering...