Oct. 7: The Lost Symbol

Robert Langdon's friend, whose name is Peter Solomon, in question is a Mason of the highest degree (33rd) and had given Langdon a box to keep safe, which Peter's assistant asked Langdon to bring to the capitol building (where he's going to give a speech). Upon arriving, Langdon finds out that there isn't a speech for him to give and that Peter's hand was cut off and placed in the center of the capitol building.