In the winter of 1282, as snow and ice ravage East Anglia, seven abbots are riding to meet a papal legate in Norfolk, each hoping to make a case for being raised to a bishopric at the next vacancy. One abbot grows so ill the party has detoured to Tyndal Priory. Despite the limited care Sister Anne can offer, he dies a horrible death. After another abbot becomes ill and dies, followed by another, Sister Anne struggles to determine what killed these men--or who?