When the BAU investigates victims of possible ritualistic murders in Utah, clues lead them to believe that they are looking for a serial killer who holds a deep fascination of the Salem witch trials. Also, Garcia prepares for a "Day of the Dead" celebration over at her apartment.
- John Lee Ames - Parker Mills
- Caitlin Carmichael - Kylie Carpenter
- Peggy Dunne - M.E. Linda Grunwell
- Jeff Griggs - Herbert Sykes
- James Immekus - Leland Duncan
- Tom Irwin - Sergeant Joe Mahaffey
- Aubrey Manning - Charlotte Novak
- Sarah Jane Morris - Yvonne Carpenter
- Charlotte Ubben - Gloria Carlyle
- Spencer Reid: "After all, what are men but a horde of ghosts? Oaks that were acorns that were oaks." — Walter de la Mare
- Penelope Garcia: Mitch Albom said, "Death ends a life, not a relationship."
- Caitlin Carmichael, the actress who portrays Kylie Carpenter, previously appeared on Criminal Minds, starring as Louisa Bonner in the Season Four episode Roadkill.
- Cooper Lupton, Harvey Redland, and Ginger Palmont, three of the names shown on Garcia's list of Salt Lake City, Utah library personnel, were previously used for the names of an assault victim mentioned in Season Eight, a victim of a spree killer in Season Seven, and a victim of a serial killer, also in Season Seven, respectively.