When a devout pilgrim returns to Shrewsbury Abbey only to die under suspicious circumstances, Brother Cadfael must navigate the intersection of faith and malice to clear the name of an innocent servant. The protagonist, Brother Cadfael, utilizes his keen observation and herbalist expertise to investigate the death of William of Lythwood, whose servant, Elave, is accused of murder. Cadfael faces opposition from rigid ecclesiastical authorities and local prejudices that threaten to condemn a man based on his status rather than evidence. The narrative unfolds through a third-person perspective that emphasizes the atmospheric tension of 12th-century monastic life and the complexities of medieval justice.

This work is widely regarded as a quintessential entry in the Brother Cadfael series, praised for its meticulous historical research and the gentle, observant nature of its protagonist. Readers often note the author's ability to weave intricate puzzles into the fabric of medieval life without sacrificing character depth. The narrative is frequently cited for its balanced approach to moral dilemmas, where the search for truth often clashes with the rigid expectations of the church. The series maintains a consistent reputation for providing a calm yet intellectually stimulating experience that transports the reader directly into the heart of the 12th century.