Ton b cu chuyn xy ra trong khong thi gian 12 ting ti Washington, D.C., v tp trung vo Hi Tam im.6 Robert Langdon c triu tp thuyt ging ti national Statuary Hall thuc united states Capitol, vi mt giy mi t thy gio ca mnh, mt thnh vin ng cp 33 trong hi Mason tn l Peter solomon ng thi cng l trng Hip hi Smithsonian. Solomon yu cu Langdon mang theo mt gi nh m ng ta nh Langdon lu gi vi nm trc . Tuy nhin, khi n khn phng, thay v gp khn gi, Langdon nhn c mt c in thoi t ngi m ng ta cho l thuc vn phng ca Solomon v sau nghe thy ting ht Capitol Rotunda. Khi chy ti ni, Langdon nhn thy tay phi ca Peter Solomon b cht t gia phng. bn tay c cc vt xm trn cc ngn v Langdon nhn ra y l biu tng ca 39;Mt th39;, dng nh ngn tay ch thng ln bc ha The Apotheosis of Washington trn vm mi ca nh Capitol. Langdon nhn ra rng bn mnh b bt cc v cht t tay v k bt cc mun Langdon tm ra Kim t thp Mason v theo tn ngng ca nhng ngi Mason, kim t thp ny c ct giu u ti Washington D.C v tm ra t b tht lc m k bt cc quyt nh tm kim.