1979. Agent Holden Ford is attached to the FBI's Behavioral Sciences Unit, headed by veteran agent Bill Tench. A new type of killer is emerging, one that kills regularly and without apparent motive. Due to the lack of motive, it is difficult to profile and apprehend the perpetrator in a murder investigation. In order to reduce this knowledge deficit, Tench and Ford set out to question incarcerated 'sequence killers' and build up a database of their backgrounds, behaviors, drivers and motives in order to make apprehending such criminals easier in future.