An Unkempt Man enters a confessional inside a Catholic church and addresses Father Brown in mumbled, hushed tones. As the church choir practices singing a hymn, Brown is dragged to nearby woods, strapped to a vertical pole and burned alive atop a man-made pyre of stacked wood.
As the Black family relaxes at home on a Sunday morning, a small bird flies into a glass pane and knocks itself unconscious. Jordan grows concerned when the bird stops breathing. Later, Catherine tells Frank that she and Jordan discussed the subject of death, during which she "mustered all of her clinical powers" and told Jordan that her mother and father would live forever.
Frank meets with fellow Millennium Group member Ardis Cohen at the church where Brown was killed. The homicide resembles similar killings that took place in 1992. At that time, several clergymen were murdered in a somewhat identical ceremonial fashion - straight out of the Middle Ages.
The Unkempt Man approaches Reverend Crane as he plays golf on a remote fairway. Using a club, the killer strikes his prey in the head, rendering him unconscious. Crane's body is discovered floating in a water hazard, his body strapped to a wooden stump. Frank discovers a woman's engagement ring lying in the grass near the hazard. On the ring are engraved the initials "J.W.M."
The Unkempt Man attacks a secretary, Beatrice Crowley, at St. Alban's Church, and makes off with old christening records from a file cabinet. Frank realizes that the killer is having difficulty locating his next victim. He also believes the perpetrator is not interested in killing men - but in killing faith. A fingerprint is lifted from the crime scene, but the elliptical patterns appear to be mutilated - as if the killer's hands had been burned in a fire.
The Unkempt Man locates his next victim, Reverend Harned, at his home in Rockford, Illinois. Beatrice Crowley, hospitalised but expected to recuperate, remembers Harned as one of the reverends who performed the christenings. Frank and Cohen rush to Harned's home, but they arrive too late. They discover the Reverend's butchered body on the living room floor.
Frank realises the killer has "come home." He asks a detective to search Rockford police records for any accidents involving the deaths of family members, in which the father survived. The database produces the name of Galen Calloway, who lost his wife and six-year-old daughter in a house fire. Calloway had been employed as a teacher of religious studies at a Catholic High School. His mother's maiden name, Janice Mosier, matches the initials engraved on the ring.
With several pounds of explosives strapped to his body, Calloway enters a church and takes parishioners hostage. Frank enters the building and successfully talks him out of detonating the bomb. Police rush in and place Calloway under arrest.
At home, Frank tells Catherine he understood Calloway's pain-and fears the same sense of hopelessness, of nothingness, should he lose a member of his family. He decides to tell Jordan the truth about death.
Fade to black...