The chief of the FBI’s counter-terrorism unit, John O’Neill, invites rookie Muslim-American agent, Ali Soufan, onto his squad. Fighting to get information from the CIA, they soon realize their work is just beginning…as two American embassies are bombed.

Following the simultaneous embassy bombings in Kenya and Tanzania, the FBI begins its investigation on the ground, while the CIA starts working on a retaliation plan.

The FBI finds one of the surviving terrorists and discovers a game changing lead in Nairobi, while the CIA’s retaliation plan in approved.

Continuing to keep information from the FBI, Schmidt is fired from Alec Station. Diane makes an important discovery about the owner of the phone number Owhali gave Chesney. O'Neill searches for solace in his faith as his personal and professional lives crumble before him.

The CIA and FBI are on high alert as threats surrounding the new millennium abound. O’Neill and Soufan raid an AQ cell in Brooklyn. The CIA continues to hide vital information from the FBI while they track suspicious individuals entering the U.S.

Vince continues asking for permission to share Mihdhar’s visa with the FBI. O’Neill loses his briefcase and an investigation into his handling of classified materials begins. A boy, radicalized after the CIA’s retaliation attack killed his friend, travels to Yemen to start his own martyrdom journey.

O’Neill and Soufan travel to Yemen to begin the investigation into the bombing of the U.S.S. Cole. The FBI becomes aware of a meeting in Malaysia and of Khallad, without knowing the CIA has been aware of both of those things for months.

The CIA becomes aware that Hazmi and Mihdhar are gone and must relay that to the FBI. O’Neill accepts a job as head of security at the World Trade Center. Soufan is sent back to Yemen. Hazmi, Mihdhar and Atta head to Vegas for a final indulgence.

Nobody can get a hold of O'Neill on Sept. 11, 2001; Soufan's evacuation from Yemen stops short as the CIA Station Chief gives him the answers he has been seeking from the CIA; Schmidt is reinstated into Alec Station; Soufan interrogates Abu Jandal.