It's a year after Teri Bauer's murder, and Kim's estranged from Jack, who has left CTU, until a call for help from President David Palmer.
Jack carries a package that he hopes will prove his loyalty to Wald's people; Kim tries to protect Megan from her father; Palmer has a problem with a skeptical reporter.
Kim makes contact with Jack, who tries to warn the immediate target; a new lead detours Mason's plans; Kate is asked to remain calm in the face of disturbing news.
Mason makes hard choices to retrieve vital information; Reza joins Kate on an errand; Jack gets closer to Wald; Kim urges Carla to take a stand for Megan.
Mason prepares to interrogate an old adversary; Jack gets more disturbing news from President Palmer; Tony goes to the Warner house to talk to Reza.
Nina tries to set the rules as Jack begins his interrogation; Kim reaches Megan; Reza asks for a lawyer; the president learns that one of his orders has been countermanded.
Finesse rather than force is required once Jack and Nina reach Visalia; Palmer directs his Chief of Staff to investigate Sherry's charge; Mason calls his estranged son; Warner and Reza are taken to CTU.
Stanton expresses concern over the presence of Sherry, who offers to deal with the detained reporter; transit of the bomb is interrupted; Tony hears a confession from Bob Warner.
Palmer IDs a person working against him; CTU learns the source of the plane's problems; Mason tries a different tack with Warner and Reza; Kate is questioned about her father's files.
Palmer meets the press to respond to Weiland's report; a tattoo proves a telling clue about who brought the plane down; Miguel hits on a plan to delay his and Kim's return to L.A..
Ali assigns Marie another duty to complete their mission; Palmer orders the interrogation of Stanton; Kate takes a lead role in getting to Ali; Sherry lobbies for more inclusion.
Warner gives some history on Marie, who talks to Kate; Jack explores a suspect's vulnerability; Mason tells Tony to stop searching for Kim; Lynne investigates a suspicion about Sherry.
Kim finds a level of comfort in her new environs; CTU experiences a power struggle; an insider reveals that the bomb has more protection than was previously believed.
Mason notes his own slowdown; Kate is drafted to help interrogate two suspects; Sherry Palmer tells her story to the president; Michelle has words with a new arrival at CTU.
The planned detonation time is determined; Ali's effects yield clues regarding the bomb's source; Jack has a conversation with Kim; Palmer makes a bold move to reassure the public.
Carrie criticizes Michelle's interrogation of Ali; the president formulates a response to those behind the bomb; and another violent incident at CTU puts Jack and Tony at odds.
Jack receives a surprising ally before meeting with the surviving member of Coral Snake, who explains the purpose behind the bomb; the VP expresses concern about Palmer's capability; Carrie shares suspicion about Michelle with Tony.
Kim comes clean with the cops; Michelle takes further risks for Jack; the president moves to curb civil unrest on the East Coast, while facing pressure to lock in his retaliatory plans.
Jack's resolve is tested by a bomber hoping to keep his plan intact; Tony meets the source of stress between Carrie and Michelle; a presidential advisor's loyalty is questioned.
The unavailability of the vice president raises curiosity in Palmer; Carrie plays politics when Tony disobeys orders; one presidential adviser wavers as another takes a fall. Chappelle:
Tony and Chappelle face off over the chip, the status of which Jack reports to Palmer, whose earlier actions regarding the bomb come to bear in a meeting with his cabinet; Kim is returned to the scene of a crime after speaking with Jack.
CTU declares Jack's quest over, as staffers are informed of a major D.C. shake-up; two key players question their trust in each other; Palmer lobbies for an ally; Tony takes a page from Jack's book.
Chappelle's unavailability prompts Division to question Tony, who puts Michelle in position to circumvent their command; Palmer is asked to perform a final executive action; Jack proposes a deal between conspirators.
Michelle and Tony benefit from new evidence against Kingsley, who reassures his conspirators; and Bob Warner confronts Marie