The team struggles because the perpetrator doesn't fit the standard profile of a male arsonist motivated by power or revenge. Dr. Spencer Reid eventually identifies the motive as —a form of Obsessive-Compulsive Disorder (OCD) involving religious or moral obsession.
Agent Hotchner confronts Clara, attempting to talk her down to buy time. When she refuses to stop, Hotchner shoots her in the leg, allowing the team to save the students. Criminal Minds Season 1 Episode 2: "Compulsion" summary CompulsionCriminal Minds : Season 1 Episode 2
The investigation leads to , a chemistry student who survived a traumatic house fire as a child. She believes she is testing her victims' purity through fire. The team struggles because the perpetrator doesn't fit
The team originally misinterprets a distorted tip-line message as "I do this for Karen," but later realizes she is saying "Charon"—the ferryman of the dead in Greek mythology. The Unsub: Clara Hayes Agent Hotchner confronts Clara, attempting to talk her
Fires are set in patterns of three (e.g., the first on March 3rd at 3:00 PM), and the unsub performs ritualistic actions in threes, such as turning doorknobs or repeating words.
The unsub is obsessed with the number three, believing it has divine significance.