The Capitol Building, Washington DC: Harvard symbologist Robert Langdon believes he is here to give a lecture. He is wrong. Within minutes of his arrival, a shockiing object is discovered. It is a gruesome invitation into an ancient world of hidden wisdom.

When Langdon's mentor. Peter Salomon -prominent mason and philantropist- is kidnapped. Langdon realizes that his only hope of saving his friend's life is to accept this mysterious summons.

It is to take him on a breathless chase through Washington's dark history. All that was familiar is changed into a shadow, mythical world in which Masonic secrets and never-before-seen revelations seem to be leading him to a single impossible and inconceivable truth.