While Cadfael has bent Abbey rules, he has never broken his monastic vows--until now. Word has come to Shrewsbury of a treacherous act that has left 30 of Maud's knights imprisoned. All have been ransomed except Cadfael's secret son, Olivier. Conceived in Cadfael's soldiering youth and unaware of his father's identity, Olivier will die if he is not freed.
In the autumn of 1145, Brother Cadfael finds himself in an awkward position. Receiving word that the son he had during the Crusades -- before he was a monk -- is in peril, Cadfael decides to attend a peace conference that might result in the young man's freedom. But to get there, Cadfael must leave the monastery without his abbot's permission.