An Excellent Mystery is the eleventh novel in Ellis Peters' Chronicles of Brother Cadfael, set in 1141 during the Anarchy, the civil war between Empress Maud and King Stephen. Two monks arrive at Shrewsbury Abbey bringing news of the conflict that destroyed Winchester and their priory: Brother Humilis, handsome, gaunt, and gravely ill, and Brother Fidelis, youthful and completely mute.
From the moment Cadfael meets them he senses something deeper than shared vows binds the two men, though what it is he can only guess. Their arrival draws the attention of a young noble searching for his one true love, a woman wronged years earlier when Humilis chose holy orders over marrying her, and who has since vanished. Notably, it is the one entry in the series that is not built around a murder, turning instead on a quieter, more personal mystery of identity and devotion.