Stiles and Lex are on a plane. Lex sees someone whom he thinks looks suspicious and he notices that they're not on the right course. And when they learn that the pilot is not answering when he is called, they call in to say that they may have been hijacked. So when word gets to Gage, he has Haisely find out what is going on. Have they been taken over by someone who plans to use the plane as a weapon? If so do they shoot it down? Meanwhile Stiles and Lex try to see if they can regain control of the plane.
The Agency discovers that a rogue agent kept an Iraqi man locked in a house for six years, believing he was a double agent, so Gage decides to return the man to his homeland, only to put Stiles' life in danger.
While the president prepares to meet with Russian negotiator Dimitri Allovich to sign a nuclear-arms treaty, Allovich's daughter rides with the president's brother when she dies in a motorcycle accident.
When the wives of several American servicemen who are overseas are being attacked, the Agency tries to help the FBI find out who is doing this. When they find him, he is unable to talk so with evidence they found on him, they learn that someone in the Spanish government gave him the info. So Stiles, Lex and Teri go to Spain to find out who it is. During their investigation, they encounter a Spanish security officer who is also doing the same thing. And he has narrowed the leak to the Minister of Defense. At the same time Gage is being told to back off.
When members of the Saudi Royal Family are being killed, they accuse the Americans. The Agency investigates and discovers circumstantial evidence that the killings are being done by private contractors. Who were hired by a billionaire whose family was killed in the World Trade Center. They try to get evidence against them but they prove to be too formidable.