Norway, 1204. A civil war between the birkebeiners —the king's men— and the baglers —supporters of the Norwegian aristocracy and the Church— ravages the country. Two men must protect a baby, the illegitimate son of King Håkon, who will be the future king and peacemaker, from those who want to kill him.

Harvard symbologist Robert Langdon works with a nuclear physicist to solve a murder and prevent a terrorist act against the Vatican during one of the significant events within the church.