In honor of her husband, young, beautiful, and wealthy widow Judith Perle donates a house to the Abbey at Shrewsbury - for the annual rent of one white rose. Judith has no shortage of suitors, and if she remarries, her dowry would be all the greater if the house were returned due to non-payment of rent. So when a priest charged with delivering the rose is found murdered, and the rose bush is found hacked to pieces, Brother Cadfael finds he must root out a killer.