The BAU travel to Detroit, Michigan, where the fire department has noticed a three year trend of the three days leading up to Halloween where a victim each day has been burned alive in an abandoned building located somewhere in the Rivertown district of town. The unsub used gasoline as an accelerant. The victims are seemingly unconnected. The BAU believe the first victim may provide some clues as to why the unsub is committing these violent murders. Using the visual memory technique, Rossi, in interviewing Kierston Torrell, the wife of the latest victim, discovers some clues as to the unsub's identity. Cross checking those that volunteer for a community organization called Detroit's Finest, which has been monitoring arsons in relation to the historic pre-Halloween fire rituals, with those that work with fire of sort sort comes up with the unsub's identity and the fact that his victims were not chosen at random. They also determine that he has an ultimate target whose identity they have to find out solely from photographs they have of her.