Set in 1979, the series centers on the inquisitive and skilled FBI Agent Bill Tench (McCallany). Along with fellow serial killer investigator in the behavioral science unit, FBI agent Holden Ford (Groff), Tench interviews serial killers to help them solve current murders.
In 1977, frustrated FBI hostage negotiator Holden Ford finds an unlikely ally in veteran agent Bill Tench and begins studying a new class of murderer.