When a flood threatens to engulf Shrewbury Abbey, the monks quickly remove all the sacred objects, including the precious relics of St. Winifred. After the deluge, it is discovered that those relics have been stolen. While trying to solve the crime, Brother Cadfael (Derek Jacobi) must protect the truth about the relics (which he uncovered in the previous Cadfael episode "A Morbid Taste for Bones"). He must also discern the link between the robbery, the kidnapping of a slave girl (Louise Delamere), the horrible confessions of a penitent monk (Julian Firth), and a thread of fabric found upon a corpse. Adapted by Ben Rostul from the novel by Ellis Peters, the 90-minute Cadfael drama "The Holy Thief" originally aired in England on June 23, 1998, and shortly thereafter was seen in America as part of PBS' Mystery anthology.