The BAU arrives in a mid-sized city rattled by three unexplained fires in as many weeks. Each blaze leveled a different type of building—a warehouse, a church basement, and most recently, a small library. No accelerants were found, no faulty wiring, nothing to suggest a typical arson. What was found unsettled everyone: burned-in symbols on the floors, shapes too precise to be accidents. The fire marshal insists the patterns are “freak coincidences,” but Reid knows better. He’s already sketching them into his notebook, tracing the sequence, muttering theories under his breath while the rest of the team interviews locals.