Special Agent Jill Church is assigned to keep tabs on Stillwater. While the FBI brass are playing politics with the press, Stillwater and Church discover a disturbing link to a cult responsible for the sarin attacks on a Japanese subway.

Furious at Stillwaters unorthodox methods, the FBI demands his immediate arrest. Now suspended from the case, Church knows that she and Stillwater are the only ones who can stop the Serpent from releasing sarin gas at a concert. 21,000 lives are at stakeincluding her own sons.