James Donnelly, an Irish writer, receives a mysterious postcard from a recently deceased friend, which sets him off on a hazardous quest. The pursuit of the truth leads Donnelly and his Icelandic assistant around the streets of post-9/11 New York, ever closer to an ancient secret regarding Abraham, forefather of Jews, Muslims, and Christians, with possible impact on modern perception of religious matters. Can the cessation of conflict between the religions really be within reach?