Special Agent Frank Pellegrino and his colleagues struggle with lessons learned in their 25-year fight against terrorism.

The organized crime division gears up for a takedown of the mob; the gang squad raids housing projects in Spanish Harlem after the death of a police officer.

After receiving intel, the FBI works to stop an attack on the subways; the JTTF meets with a former terrorist, while awaiting verdicts.

After ISIS strikes in Paris and San Bernardino, the FBI in New York works to prevent an attack on the city during the holidays.

Squad C-19 chases the Cannibal Cop; agents in Crimes Against Children deal with the psychological impact of their cases.

The cyber division takes down a Russian national; an openly gay agent struggles with the Orlando nightclub shooting; a radical approach to dealing with an ISIS supporter.