Jack establishes his cover with a small group of domestic terrorists by giving the head of Marshall Goren. He learns that their target is CTU. Kim takes Megan and runs from the house, but Gary pursues them. Palmer and Eric Rayburn disagree over a possible evacuation.
Chloe secretly helps Jack track one of the terrorists. Navi and Dina Araz order Behrooz to bring his girlfriend, Debbie, to their home to find out what she knows. Curtis is forced to interrogate Secretary Heller's son, Richard, to see if he was involved in his father's kidnapping.
Jack conceals himself in the airport hangar, surveying the Russian separatists and feeding information to Curtis and his assault team. The terrorists continue to execute hostages in an attempt to make PresidentLogan give in to their demands to nullify the treaty. Martha discovers that all the traces of her conversation with David Palmer might not have been erased.
CTU and Jack Bauer race to find Abu Fayed before he is able to detonate a suitcase nuke. Jack must make a difficult choice between his prisoner and his partner. The President's sister makes calls to her brother on behalf of Rezani, while Wayne Palmer faces the toughest hour of his Presidency, as a nuclear device detonates in Valencia.
Using a CIP device constructed by the abducted Michael Latham, Tony gives a demonstration of the potential destruction in the device he now controls. Henry Taylor pays a visit to Samantha Roth to question her about his son Roger's death. Jack and Renee pursue one of Tony's men and confront Almeida himself, face-to-face.