Parsons gripes about his project; then a bomb explodes, killing the SecNav; Gibbs volunteers for a spec op, which takes him to Iran, where he runs into Parsons, and where they investigate. Tony tries to pursue Ziva in Israel. [Continued.]

Tony searches for Ziva in Israel and elsewhere; he finally finds her, but he returns without her. Gibbs, Fornell, and others work hard on the case of the bomber. McGee makes a huge discovery, which allows Gibbs to solve and to take a shot.

An explosion and a fire damage an offshore drilling platform near the Virginia Capes, killing one (a major in the US Marine Corps Reserve) and injuring many others; Gibbs and company, along with Abby of the CGIS, investigate. The CEO and the chief legal counsel of the oil company assure the SecNav and Gibbs of their utmost cooperation. Tony and McGeek trace one lead, which appears to reach a dead end, but which leaves egg on McGoo's face; Gibbs and the other Abby suspect that the target was not the platform but rather the dead victim. Tony and McGee plus Gibbs and Borin revisit the dead end, where they make a major discovery; Abby puts things together in her shop; Borin questions the corporate lawyer in Gibbs's chat room and brings the investigation to a close. Meanwhile Halloween pranks abound, eventually tripping even Tony.

A Navy petty officer dies of gunfire in a park in Washington, DC; Gibbs and company investigate; Hollis helps. The gang find an accessory for hire to a terrorist. An explosion kills six and injures 22, including Delilah. [Continued.]

Ellie's gut says that Parsa is in his home district in NW Pakistan; there a SEAL team captures him alive. Gibbs, McGee, and Ellie fly to an aircraft carrier, where Gibbs and Ellie question him. Ellie gets into a bind, but Gibbs saves her.

Gibbs and McGee are shot down in a Naval helicopter over remote parts of Russia while on a mission to escort an NCIS computer geek safely home. Meanwhile, the gang at home anxiously work to help bring them all home safely.

A Navy Commander is murdered near the White House, it is learned that he was on his way to talk to the President. Gibbs and his team must determine if it is because of his relationship with the President or because of his marital problems.