Mark Zoubianis, a hacker friend of Trish’s, is settling in to watch the playoff game when Trish calls. She asks him to find the origin of a specific document: the heavily redacted file that contained all of the keywords for which Katherine was looking. Mark reluctantly agrees to do it, thinking that he can finish the task in just a few minutes and then return his attention to the game.

Langdon follows Director Sato and Capitol Police Chief Anderson into the crypt beneath the Capitol Building. Langdon intellectually understands that the area is not a literal crypt for bodies, and that it is instead used as a storage area. Still, he cannot suppress a chilling emotional reaction to the crypt, due to his lifelong claustrophobia: a result of his traumatic fall into a well when he was a child. As they pass doors marked with either a S or an H, Langdon realizes that the doors are given their designation based on whether they are on the Senate side or the House side of the building. They come to a door marked SB. Anderson explains the letters stand for “Senate Basement.”