The story is set in 1138 in a lull in the civil war between King Stephen and Empress Maud. The Monastery of St Peter and St Paul in Shrewsbury is facing its own turmoil as Abbot Heribert has been called to a council, and it is expected that he will be replaced as Abbott, So Prior Robert is preening himself and making his presence felt as the expected future Abbott.
Gervase Bonel has left his property, Mallilie, to the monastery, but the agreement cannot be ratified as St Peter and St Paul doesn’t currently have a confirmed Abbott. Bonel is murdered before the agreement can be ratified, and the weapon used is a poison, containing Monk’s Hood, which Cadfael has prepared as a rubbing liniment.
Suspicion for the murder immediately falls on Bonel’s step-son Edwin – He was promised Bonel’s property until they fell out with each other. Cadfael quickly establishes Edwin’s innocence, but Edwin must stay in hiding as an enthusiastic sergeant is convinced of his guilt and keen to lay hands on him.
There are other members of Bonel’s household who could be guilty of the murder. Richildis is Bonel’s wife and Edwin’s mother and also happens to be Cadfael’s first love from their teen years. Could Richildis have murdered her husband to secure Mallilie for her son? Aelfric’s status has been changed from free to villain due to a quirk in the law and Bonel’s pig-headedness. Meurig is Bonel’s bastard son and therefore not entitled by English law to inherit property, he appears to have nothing to gain by his father’s death.
Cadfael travels to Mallilie and the Welsh/English border and eventually, with a little help from deputy Sheriff Hugh Beringar, identifies the real murderer and clears Edwin’s name.
At the end of the book, Abbott Heribert returns with a surprise announcement regarding the abbacy of St Peter and St Paul.
Book Published 1980