After the violence of civil war in the spring, Shrewsbury has enjoyed a quiet summer and a good harvest. But, as Cadfael reflects ruefully, such a peaceful state of affairs cannot be expected to last. He's right. The trouble begins when Gervase Bionel, rich lord of the manor, proposes to sign all his property over to the Abbey. A welcome gift, but when Bonel is found poisoned, foul play is suspected somewhere along the line. Cadfael is sure that the obvious suspect is not the right one, but are his powers of detection strong enough to lead him through the maze of clues to the truth?