Four more "suitcase nukes" are out there, and Jack's only lead takes him to the home of his brother.

Family troubles: Jack with his brother and father while Morris worries about his own brother.

The President meets with a known terrorist, while Jack searches for Morris, Fayed seeks a trigger, and Tom Lennox makes a choice.

Jack looks for a Russian national as his father plots with shadowy patriots. Meanwhile, the President and the Constitution may be in danger.

While Jack looks for Gredenko and tries to save Josh, White House intrigue deepens.

Jack's search takes him to the home of an old enemy, while a bomber slips into the White House.

Russian ire worries the White House, while the Chinese take on CTU, and the damaged circuit board is in surprising hands.

Russia presses the White House, while Jack must try to thwart the Chinese and his oldest antagonist simultaneously.

In order to prevent a war with Russia, the White House orders a trade of Jack's nephew for the circuit board, and puts Jack in custody so he cannot stop the exchange.

Jack rushes toward his nephew and his oldest antagonist, as a Chinese sub and F-18s race for the same destination. Chloe faints. Can Jack find any peace?